1. phát tri?n quy trình x? ly ??ng l?nh

X? ly ??ng l?nh th??ng s? d?ng ph??ng pháp làm mát b?ng nit? l?ng, có th? làm mát ph?i xu?ng d??i -190oC. C?u trúc vi m? c?a v?t li?u ???c x? ly thay ??i ? nhi?t ?? th?p và m?t s? tính ch?t ???c c?i thi?n. X? ly ??ng l?nh l?n ??u tiên ???c Liên X? c? ?? xu?t vào n?m 1939. Ph?i ??n nh?ng n?m 1960, Hoa K? m?i áp d?ng c?ng ngh? x? ly ??ng l?nh vào ngành c?ng nghi?p và b?t ??u s? d?ng ch? y?u trong l?nh v?c hàng kh?ng. Vào nh?ng n?m 1970, nó m? r?ng sang l?nh v?c s?n xu?t máy móc.

Theo các ph??ng pháp làm l?nh khác nhau, nó có th? ???c chia thành ph??ng pháp l?ng và ph??ng pháp khí. Ph??ng pháp l?ng có ngh?a là v?t li?u ho?c ph?i ???c nhúng tr?c ti?p vào nit? l?ng ?? làm ngu?i ph?i ??n nhi?t ?? nit? l?ng, và ph?i ???c gi? ? nhi?t ?? này trong m?t th?i gian nh?t ??nh, sau ?ó ???c ??a ra ngoài và nung nóng ??n m?t nhi?t ?? nh?t ??nh. . R?t khó ?? ki?m soát t?c ?? t?ng và gi?m nhi?t ?? theo cách này, ?i?u này có tác ??ng nhi?t l?n ??n ph?i và th??ng ???c cho là có kh? n?ng gay h? h?ng cho ph?i. Thi?t b? ??ng l?nh t??ng ??i ??n gi?n, ch?ng h?n nh? bình nit? l?ng.

2. ph??ng pháp x? ly ??ng l?nhgas

Nguyên ly khí là làm mát b?ng nhi?t ?n khí hóa(chǎn) c?a nit? l?ng (kho?ng 199,54kJ/kg) và s? h?p th? nhi?t c?a nit? ? nhi?t ?? th?p. Ph??ng pháp khí có th? làm cho nhi?t ?? ??ng l?nh ??t t?i - 190oC, do ?ó nit? ??ng l?nh có th? ti?p xúc v?i v?t li?u. Th?ng qua trao ??i nhi?t ??i l?u, nit? có th? bay h?i trong h?p ??ng l?nh sau khi ???c ??y ra kh?i vòi phun. Ph?i có th? ???c làm mát b?ng nhi?t ?n c?a quá trình khí hóa(chǎn) và s? h?p th? nhi?t c?a nit? ??ng l?nh. B?ng cách ki?m soát ??u vào c?a nit? l?ng ?? ki?m soát t?c ?? làm mát, nhi?t ?? x? ly ??ng l?nh có th? ???c ?i?u ch?nh t? ??ng và ki?m soát chính xác, hi?u ?ng s?c nhi?t nh? nên kh? n?ng b? n?t c?ng nh?.

Hi?n nay, ph??ng pháp khí ???c các nhà nghiên c?u c?ng nh?n r?ng r?i trong ?ng d?ng c?a nó, và thi?t b? làm mát c?a nó ch? y?u là h?p l?nh có th? l?p trình v?i nhi?t ?? có th? ki?m soát ???c. X? ly b?ng ph??ng pháp ??ng l?nh có th? c?i thi?n ?áng k? tu?i th?, kh? n?ng ch?ng mài mòn và ?? ?n ??nh kích th??c c?a kim lo?i ?en, kim lo?i màu, h?p kim kim lo?i và các v?t li?u khác, mang l?i l?i ích kinh t? ?áng k? và tri?n v?ng th? tr??ng.

C?ng ngh? ??ng l?nh c?a cacbua xi m?ng l?n ??u tiên ???c báo cáo vào nh?ng n?m 1980 và 1990. C?ng ngh? c? khí c?a Nh?t B?n n?m 1981 và C?a hàng máy hi?n ??i c?a Hoa K? vào n?m 1992 báo cáo r?ng hi?u su?t c?a cacbua xi m?ng ?? ???c c?i thi?n ?áng k? sau khi x? ly ??ng l?nh. T? nh?ng n?m 1970, c?ng vi?c nghiên c?u v? x? ly ??ng l?nh ? n??c ngoài ?? có k?t qu?. Liên X? c?, Hoa K?, Nh?t B?n và các n??c khác ?? s? d?ng thành c?ng ph??ng pháp x? ly ??ng l?nh ?? c?i thi?n tu?i th? c?a d?ng c? và khu?n, kh? n?ng ch?ng mài mòn c?a ph?i và ?n ??nh kích th??c.

3. t?ng c??ng c? ch? ?i?u tr? ??ng l?nh

Gia c? pha kim lo?i.

Co trong cacbua liên k?t có c?u trúc tinh th? fcc pha α (fcc) và c?u trúc tinh th? l?c giác ?óng gói kín ε Pha (hcp). ε- T? s? Co α- Co có h? s? ma sát nh? và ch?u mài mòn m?nh. Trên 417 ℃ α N?ng l??ng t? do c?a pha th?p nên t?n t?i d?ng pha Co α. D??i 417 ℃ ε N?ng l??ng t? do c?a pha th?p, pha ?n ??nh ? nhi?t ?? cao α Chuy?n pha sang pha có n?ng l??ng t? do th?p ε Pha. Tuy nhiên, do các h?t WC và α S? t?n t?i c?a các d? nguyên t? trong dung d?ch r?n trong pha có h?n ch? l?n h?n ??i v?i s? chuy?n pha, làm cho α → ε Khi ?i?n tr? thay ??i pha t?ng và nhi?t ?? gi?m xu?ng d??i 417 ℃ α thì pha kh?ng th? chuy?n hoàn toàn. thành ε Pha. X? ly ??ng l?nh có th? làm t?ng ?áng k? α Và ε S? chênh l?ch n?ng l??ng t? do hai pha, do ?ó làm t?ng ??ng l?c c?a s? thay ??i pha ε Bi?n s? thay ??i pha. ??i v?i cacbua liên k?t sau khi x? ly ??ng l?nh, m?t s? nguyên t? hòa tan trong Co k?t t?a ? d?ng h?p ch?t do gi?m ?? hòa tan, có th? làm t?ng pha c?ng trong ma tr?n Co, c?n tr? s? di chuy?n l?ch v? trí và ?óng vai trò t?ng c??ng pha th? hai. v?t r?t nh?.

T?ng c??ng ?ng su?t d? b? m?t.

Nghiên c?u sau khi x? ly ??ng l?nh cho th?y ?ng su?t nén d? trên b? m?t t?ng lên. Nhi?u nhà nghiên c?u tin r?ng m?t giá tr? nh?t ??nh c?a ?ng su?t nén d? trong l?p b? m?t có th? c?i thi?n ?áng k? tu?i th? c?a nó. Trong quá trình làm ngu?i c?a cacbua xi m?ng sau khi thiêu k?t, pha liên k?t Co ch?u ?ng su?t kéo, và các h?t WC ph?i ch?u ?ng su?t nén. ?ng su?t kéo có tác h?i l?n ??i v?i Co. Do ?ó, m?t s? nhà nghiên c?u tin r?ng s? gia t?ng ?ng su?t nén b? m?t do làm ngu?i sau s? làm ch?m l?i ho?c bù ??p m?t ph?n ?ng su?t kéo t?o ra b?i giai ?o?n liên k?t trong quá trình làm ngu?i sau khi nung k?t, ho?c th?m chí ?i?u ch?nh nó ?? ?ng su?t nén, gi?m s? phát sinh các v?t n?t nh?.

Các c? ch? t?ng c??ng khác

Ng??i ta tin r?ng η Các h?t pha cùng v?i các h?t WC làm cho ma tr?n tr? nên ch?t ch? và ch?c ch?n h?n, và do η S? hình thành c?a pha tiêu th? Co trong ma tr?n. S? gi?m hàm l??ng Co trong pha liên k?t làm t?ng ?? d?n nhi?t t?ng th? c?a v?t li?u, và s? gia t?ng kích th??c h?t cacbua và s? k? nhau c?ng làm t?ng ?? d?n nhi?t c?a ch?t n?n. Do s? gia t?ng c?a ?? d?n nhi?t, s? t?n nhi?t c?a các ??u dao và khu?n d?p nhanh h?n; C?i thi?n kh? n?ng ch?ng mài mòn và ?? c?ng nhi?t ?? cao c?a d?ng c? và khu?n. Nh?ng ng??i khác tin r?ng sau khi x? ly ??ng l?nh, do Co co l?i và c? ??c, vai trò v?ng ch?c c?a Co trong vi?c gi? các h?t WC ???c t?ng c??ng. Các nhà v?t ly cho r?ng vi?c làm l?nh sau ?? làm thay ??i c?u trúc c?a các nguyên t? và phan t? c?a kim lo?i.

4.M?t tr??ng h?p YG20 Cold Heading Die v?i Cryogenic Treatment

Các b??c v?n hành c?a x? ly ??ng l?nh ván khu?n tr? thép YG20:

(1) ??a khu?n ngu?i thiêu k?t vào lò x? ly ??ng l?nh;

(2) Kh?i ??ng lò tích h?p ? ??ng l?nh, m? nit? l?ng, gi?m xu?ng -60oC ? t?c ?? nh?t ??nh và gi? nhi?t ?? trong 1h;

(3) Gi?m xu?ng -120oC ? t?c ?? nh?t ??nh và gi? nhi?t ?? trong 2 gi?;

(4) Gi?m nhi?t ?? xu?ng -190oC ? t?c ?? làm mát nh?t ??nh và gi? nhi?t ?? trong 4-8h;

(5) Sau khi b?o qu?n nhi?t, nhi?t ?? s? ???c t?ng lên 180 ℃ theo 0,5 ℃ / phút trong 4 gi?

(6) Sau khi thi?t b? ch??ng trình hoàn thành, thi?t b? s? t? ??ng t?t ngu?n và làm mát t? nhiên ??n nhi?t ?? phòng.

K?t lu?n: ??u khu?n l?nh YG20 kh?ng qua x? ly ??ng l?nh và sau khi x? ly ??ng l?nh là ??u ngu?i Φ 3.8 Thanh vít b?ng thép cacbon, k?t qu? cho th?y tu?i th? c?a khu?n sau khi x? ly ??ng l?nh dài h?n 15% so v?i khu?n kh?ng qua x? ly ??ng l?nh .

Có th? th?y r?ng so v?i tr??c khi x? ly ??ng l?nh, coban l?p ph??ng tam m?t (fcc) trong YG20 sau khi x? ly ??ng l?nh gi?m ?áng k?, ε- S? gia t?ng r? r?t c?a Co (hcp) c?ng là ly do c?i thi?n kh? n?ng ch?ng mài mòn và ??c tính toàn di?n c?a cacbua xi m?ng.

5. H?n ch? c?a quá trình x? ly ??ng l?nh

K?t qu? ?ng d?ng th?c t? c?a m?t c?ng ty s?n xu?t d?ng c? và khu?n ?úc ? Hoa K? cho th?y tu?i th? c?a mi?ng chèn cacbua xi m?ng sau khi x? ly t?ng lên 2 ~ 8 l?n, trong khi chu k? thay b?ng c?a khu?n kéo day cacbua xi m?ng sau khi x? ly kéo dài t? vài tu?n ??n vài tháng. Trong nh?ng n?m 1990, nghiên c?u trong n??c v? c?ng ngh? ??ng l?nh c?a cacbua xi m?ng ?? ???c th?c hi?n và ?? ??t ???c m?t s? k?t qu? nghiên c?u nh?t ??nh.

Nhìn chung, nghiên c?u v? c?ng ngh? x? ly ??ng l?nh cacbua xi m?ng hi?n nay ít ???c phát tri?n và ch?a có h? th?ng, các k?t lu?n thu ???c c?ng kh?ng th?ng nh?t, c?n ???c các nhà nghiên c?u tìm hi?u sau h?n. Theo d? li?u nghiên c?u hi?n có, x? ly ??ng l?nh ch? y?u c?i thi?n kh? n?ng ch?ng mài mòn và tu?i th? c?a cacbua xi m?ng, nh?ng kh?ng có ?nh h??ng r? ràng ??n các tính ch?t v?t ly.

X? ly bán kính c?nh là m?t quá trình kh?ng th? thi?u sau khi mài m?n các d?ng c? CNC và tr??c khi ph?. M?c ?ích là làm cho l??i c?t m?n và m??t, ??ng th?i kéo dài tu?i th? c?a d?ng c?. Có 9 ph??ng pháp x? ly bán kính c?nh c?a d?ng c? CNC ???c Meetyou gi?i thi?u. Chúng ta h?y làm quen v?i nó.

X? ly bán kính c?nh c?a d?ng c? c?t c?a trung tam gia c?ng ?? c?p ??n quá trình san b?ng, ?ánh bóng và làm m? các d?ng c? c?t, bao g?m th? ??ng c?nh, ?ánh bóng r?nh lo?i b? phoi và ?ánh bóng l?p ph?.

1. Kh? n?ng ch?ng mài mòn v?t ly c?a d?ng c?

Trong quá trình c?t, b? m?t d?ng c? s? b? ph?i tiêu hao d?n và l??i c?t d? b? bi?n d?ng d?o d??i nhi?t ?? cao và áp su?t cao. Vi?c x? ly th? ??ng c?a d?ng c? có th? giúp c?i thi?n ?? c?ng c?a d?ng c? và tránh m?t hi?u su?t c?t s?m c?a d?ng c?.

2. Duy trì ?? m?n c?a ph?i

Các g? trên l??i c?t c?a d?ng c? s? gay mòn d?ng c? và b? m?t ph?i ???c gia c?ng s? tr? nên nhám. Sau khi x? ly th? ??ng, l??i c?t c?a d?ng c? s? tr? nên r?t m?n, hi?n t??ng x?p c?nh s? gi?m ?i t??ng ?ng và ?? bóng b? m?t c?a ph?i c?ng s? ???c c?i thi?n.

3. Lo?i b? phoi r?nh ti?n l?i

?ánh bóng r?nh d?ng c? có th? c?i thi?n ch?t l??ng b? m?t và hi?u su?t lo?i b? phoi. B? m?t r?nh càng m?n thì kh? n?ng lo?i b? phoi càng t?t và có th? ??t ???c ???ng c?t ?n ??nh h?n.

Sau khi th? ??ng và ?ánh bóng, các d?ng c? c?a máy c?ng c? CNC s? ?? l?i nhi?u l? nh? trên b? m?t. Nh?ng l? này có th? h?p th? nhi?u ch?t l?ng c?t h?n trong quá trình gia c?ng, ?i?u này s? làm gi?m ?áng k? nhi?t sinh ra trong quá trình c?t và c?i thi?n ?áng k? t?c ?? c?t.

9 lo?i ph??ng pháp x? ly bán kính c?nh

Ph??ng pháp bán kính c?nh bánh mài

?ay là c?ng ngh? th? ??ng s?m nh?t và ???c s? d?ng r?ng r?i nh?t.

Ph??ng pháp bán kính c?nh bàn ch?i nylon

Ph??ng pháp ph? bi?n là ph? m?i tr??ng mài mòn g?m các h?t m?n lên bánh xe bàn ch?i ho?c ??a bàn ch?i b?ng v?t li?u nylon và di chuy?n l?i dao c?t th?ng qua chuy?n ??ng quay t?c ?? cao c?a bàn ch?i.

Ph??ng pháp phun cát

nó ???c chia thành phun cát kh? và phun cát ??t. Nó c?ng là m?t ph??ng pháp ph? bi?n ?? x? ly bán kính c?nh. So v?i ph??ng pháp ch?i nylon, quá trình này ??t ???c ?? ??ng nh?t cao h?n c?a các c?nh.

Ph??ng pháp khu?y x? ly bán kính c?nh

Ph??ng pháp này là ??t toàn b? d?ng c? vào thùng mài mòn tr??c khi x? ly và ??nh v? ?? sau c?a d?ng c? th?ng qua c?m bi?n laser ?? ??m b?o ch?t l??ng x? ly. ?? ??c c?a l??i c?a quá trình này c?ng cao h?n so v?i ph??ng pháp dùng ch?i nylon.

Gia c?ng bán kính c?nh c? ?i?n hóa(chǎn)

?ay là m?t quá trình t?ng h?p k?t h?p gi?a gia c?ng ?i?n hóa(chǎn) và mài c? h?c. ??u tiên, lo?i b? ba via b?ng ?i?n phan, sau ?ó là mài c? h?c ?? lo?i b? màng oxit.

Ph??ng pháp laser: là c?ng ngh? th? ??ng ???c phát tri?n trên c? s? c?ng ngh? ph? laser. Nó có th? t?o ra nhi?t ?? cao trên b? m?t l??i dao b?ng tia laser, làm tan ch?y m?t s? v?t li?u và ??t ???c hi?u qu? th? ??ng hóa(chǎn) l??i dao.

Ph??ng pháp x? ly bán kính c?nh rung

 thi?t b? x? ly chính bao g?m bàn rung và bàn làm vi?c. L??i dao ???c ??t trong m?t thùng ch?a ???c n?i v?i than rung. Thùng ch?a ??y các h?t mài mòn. Các h?t mài mòn và l??i dao va ch?m liên t?c ?? lo?i b? các v?t li?u còn sót l?i trên l??i c?t th?ng qua va ch?m ?? ??t ???c s? th? ??ng c?a c?nh.

Ph??ng pháp mài mòn t? tính

?ay là quá trình x? ly bán kính c?nh, áp d?ng t? tr??ng theo h??ng vu?ng góc v?i tr?c c?a b? m?t hình tr? c?a ph?i và thêm l?c mài mòn t? tính gi?a các c?c S và N c?a t? tr??ng. Ch?t mài mòn t? tính s? ???c h?p ph? trên c?c t? và b? m?t ph?i và s? ???c b? trí thành m?t “bàn ch?i mài mòn” linh ho?t d?c theo h??ng c?a ???ng s?c t?. Máy c?t quay và rung d?c tr?c cùng lúc ?? lo?i b? kim lo?i và các g? trên b? m?t ph?i.

C?ng ngh? tia n??c mài mòn vi m?: c?ng ngh? x? ly m?i và than thi?n v?i m?i tr??ng, t?o thành tia n?ng l??ng cao r?n-l?ng th?ng qua vi?c ?i?u khi?n b? ?i?u áp và ???ng kính vòi phun, ??ng th?i th?c hi?n x? ly th? ??ng b?ng va ch?m t?c ?? cao và l?p ?i l?p l?i trên ph?i.

Etching is a technology that uses chemical strong acid corrosion, mechanical polishing or electrochemical electrolysis to treat the surface of objects. In addition to enhancing aesthetics, it also increases the added value of objects. From traditional metal processing to high-tech semiconductor manufacturing, they are all within the scope of application of etching technology.

Metal etching is a technology to remove metal materials through chemical reaction or physical impact. Metal etching technology can be divided into wet etching and dry etching. Metal etching consists of a series of chemical processes. Different etchants have different corrosion characteristics and strength for different metal materials.

Metal etching, also known as photochemical etching, refers to the removal of the protective film of the metal etching area after exposure, plate making, development and contact with the chemical solution in the process of metal etching, so as to achieve dissolution corrosion, formation of bumps, or hollowing out. It was first used to manufacture printed concave convex plates such as copper plate and zinc plate. It is widely used to reduce the weight of instrument panel or process thin workpieces such as nameplate. Through the continuous improvement of technology and process equipment, etching technology has been applied to aviation, machinery, chemical industry and semiconductor manufacturing processes for the processing of precision metal etching products of electronic thin parts.

Types of etching technology

Wet etching:

Wet etching is to immerse the wafer into a suitable chemical solution or spray the chemical solution onto the wafer for quenching, and remove the atoms on the surface of the film through the chemical reaction between the solution and the etched object, so as to achieve the purpose of etching During wet etching, the reactants in the solution first diffuse through the stagnant boundary layer, and then reach the wafer surface to produce various products through chemical reactions. The products of etching chemical reaction are liquid or gas phase products, which are then diffused through the boundary layer and dissolved in the main solution. Wet etching will not only etch in the vertical direction, but also have the effect of horizontal etching.

Dry etching:

Dry etching is usually one of plasma etching or chemical etching. Due to different etching effects, the physical atoms of ions in the plasma, the chemical reaction of active free radicals and the surface atoms of devices (wafers), or the combination of the two, include the following contents:

physical etching: sputtering etching, ion beam etching

chemical etching: plasma etching

physicochemical composite etching: reactive ion etching (RIE)

Dry etching is a kind of anisotropic etching, which has good directivity, but the selectivity is worse than wet etching. In plasma etching, plasma is a partially dissociated gas, and gas molecules are dissociated into electrons, ions and other substances with high chemical activity. The biggest advantage of dry etching is “anisotropic etching”. However, the selectivity of dry etching is lower than that of wet etching. This is because the etching mechanism of dry etching is physical interaction; Therefore, the impact of ions can remove not only the etching film, but also the photoresist mask.

Etching process

According to the type of metal, the etching process will be different, but the general etching process is as follows: metal etching plate → cleaning and degreasing → water washing → drying → film coating or silk screen printing ink → drying → exposure drawing → development → water washing and drying → etching → film stripping → drying → inspection → finished product packaging.

1. Cleaning process before metal etching:

The process before etching stainless steel or other metals is cleaning treatment, which is mainly used to remove dirt, dust, oil stains, etc. on the material surface. The cleaning process is the key to ensure that the subsequent film or screen printing ink has good adhesion to the metal surface. Therefore, the oil stain and oxide film on the metal etching surface must be completely removed. Degreasing shall be determined according to the oil stain of the workpiece. It is best to degrease the silk screen printing ink before electric degreasing to ensure the degreasing effect. In addition to the oxide film, the best etching solution shall be selected according to the type of metal and film thickness to ensure surface cleanliness. It must be dry before screen printing. If there is moisture.

2. Paste dry film or silk screen photosensitive adhesive layer:

According to the actual product material, thickness and the exact width of the figure, it is determined to use dry film or wet film silk screen printing. For products with different thicknesses, factors such as the etching processing time required for product graphics should be considered when applying the photosensitive layer. It can make a thicker or thinner photosensitive adhesive layer with good coverage performance and high definition of patterns produced by metal etching.

3. Drying:

After the completion of film or roll screen printing ink, the photosensitive adhesive layer needs to be thoroughly dried to prepare for the exposure process. At the same time, ensure that the surface is clean and free of adhesion, impurities, etc.

4. Exposure:

This process is an important process of metal etching, and the exposure energy will be considered according to the thickness and accuracy of the product material. This is also the embodiment of the technical ability of etching enterprises. The exposure process determines whether the etching can ensure better dimensional control accuracy and other requirements.

5. Development:

After the photosensitive adhesive layer on the surface of the metal etching plate is exposed, the pattern adhesive layer is cured after exposure. Then, the unwanted part of the pattern, that is, the part that needs corrosion, is exposed. The development process also determines whether the final size of the product can meet the requirements. This process will completely remove the unnecessary photosensitive adhesive layer on the product.

6. Etching or etching process:

After the product prefabrication process is completed, the chemical solution will be etched. This process determines whether the final product is qualified. This process involves etching solution concentration, temperature, pressure, speed and other parameters. The quality of the product needs to be determined by these parameters.

7. Removal:

The surface of the etched product is still covered with a layer of photosensitive adhesive, and the photosensitive adhesive layer on the surface of the etched product needs to be removed. Because the photosensitive adhesive layer is acidic, it is mostly expanded by acid-base neutralization method. After overflow cleaning and ultrasonic cleaning, remove the photosensitive adhesive layer on the surface to prevent photosensitive adhesive residue.

8. Test:

After the film is taken, the following is testing, packaging, and the final product is confirmed whether it meets its specifications.

Precautions in etching process

reduce side corrosion and protruding edges and improve metal etching processing coefficient: generally, the longer the printed board is in the metal etching solution, the more serious the side etching is. Undercutting seriously affects the accuracy of printed wire, and serious undercutting will not make thin wire. When the undercut and edge decrease, the etching coefficient increases. The high etching coefficient indicates that the thin line can be maintained and the etched line is close to the size of the original image. Whether the plating resist is tin lead alloy, tin, tin nickel alloy or nickel, the excessively protruding edge will lead to short circuit of the conductor. Because the protruding edge is easy to break, an electric bridge is formed between two points of the conductor.

improve the consistency of etching processing rate between plates: in continuous plate etching, the more consistent the metal etching processing rate, the more uniform etching plate can be obtained. In order to maintain the best etching state in the pre etching process, it is necessary to select an etching solution that is easy to regenerate and compensate and easy to control the etching rate. Select technologies and equipment that can provide constant operating conditions and automatically control various solution parameters. It can be realized by controlling the amount of copper dissolved, pH value, solution concentration, temperature, uniformity of solution flow, etc.

improve the uniformity of the metal etching processing speed of the whole plate surface: the etching uniformity of the upper and lower sides of the plate and each part of the plate surface is determined by the uniformity of the flow rate of the metal etching solution on the plate surface. In the etching process, the etching rates of the upper and lower plates are often inconsistent. The etching rate of the lower plate surface is higher than that of the upper plate surface. Due to the accumulation of solution on the surface of the upper plate, the etching reaction is weakened. The uneven etching of the upper and lower plates can be solved by adjusting the injection pressure of the upper and lower nozzles. The spray system and the oscillating nozzles can further improve the uniformity of the whole surface by making the spray pressure of the center and edge of the plate different.

Advantages of etching process

Because the metal etching process is etched by chemical solution.

maintain high consistency with raw materials. It does not change the properties, stress, hardness, tensile strength, yield strength and ductility of the material. The base processing process is etched in the equipment in an atomized state, and there is no obvious pressure on the surface.

no burrs. In the process of product processing, there is no pressing force in the whole process, and there will be no crimping, bumping and pressing points.

it can cooperate with the post process stamping to complete the personalized molding action of the product. The hanging point method can be used for full plate electroplating, bonding, electrophoresis, blackening, etc., which is more cost-effective.

it can also cope with miniaturization and diversification, short cycle and low cost.

Application field of etching processing

consumer electronics

filtration and separation technology

Aerospace

medical equipment

precision machinery

car

high end crafts

Cacbua xi m?ng là m?t lo?i cacbua xi m?ng ???c ch? t?o t? quá trình luy?n kim b?t t? h?p ch?t c?ng c?a kim lo?i ch?u l?a và kim lo?i liên k?t. B?i vì ?? c?ng và s?c m?nh t?t c?a nó, nó ???c s? d?ng r?ng r?i trong nhi?u l?nh v?c. V?i yêu c?u v? hi?u su?t nhi?t ?? cao và kh? n?ng ch?ng ?n mòn c?a v?t li?u cacbua xi m?ng ngày càng cao, hi?u su?t c?a v?t li?u cacbua xi m?ng hi?n t?i khó ?áp ?ng yêu c?u s? d?ng. Trong 30 n?m qua, nhi?u h?c gi? ?? th?c hi?n nghiên c?u th? nghi?m các h?p ch?t d?a trên WC và thu ???c m?t lo?t k?t qu? nghiên c?u.

Kim lo?i WC

WC-Co

V?t li?u xi m?ng ???c s? d?ng r?ng r?i trong cacbua vonfram là coban. H? th?ng WC Co ?? ???c nghiên c?u r?ng r?i. Vi?c b? sung CO làm cho WC có ?? ?m và ?? bám dính t?t. Ngoài ra, nh? trong Hình 13.2, vi?c b? sung CO c?ng có th? c?i thi?n ?áng k? s?c m?nh và ?? d?o dai.

Hình 13.3 Máy vi tính ?i?n t? tán x? ng??c c?a b?t WC Co cho th?y c?u trúc bên ngoài và m?t c?t ngang: (a), (b) F8; (c), (d) M8; và (E), (f) C8.

?ng ?? th?c hi?n hình ?nh ?i?n t? tán x? ng??c c?a b?t F8, M8 và C8 và các ph?n ???c ?ánh bóng c?a chúng. Nó ?? ???c quan sát th?y r?ng t?t c? các lo?i b?t có hình d?ng hình c?u ?i?n hình. B?t F8 cho th?y s? tích t? dày ??c c?a các cacbua m?n, trong khi b?t M8 và C8 cho th?y c?u trúc tích l?y t??ng ??i l?ng l?o v?i m?t s? l? chan l?ng. Trên ph?n ?ánh bóng, t?t c? các m?u cho th?y hi?n t??ng tán x? r? ràng, và ?? c?ng và kh? n?ng ch?ng mài mòn t? l? ngh?ch v?i hàm l??ng coban. ?? c?ng Vickers (HV) thay ??i t? 1500 ??n 2000 HV30, và ?? b?n g?y dao ??ng t? 7 ??n 15 MPa M1 / 2. S? thay ??i ?áng k? này là m?t ch?c n?ng c?a thành ph?n cacbua, c?u trúc vi m? và ?? tinh khi?t hóa(chǎn) h?c.

Nói chung, kích th??c h?t càng nh? thì ?? c?ng càng cao và kh? n?ng ch?ng mài mòn càng t?t. T? l? th? tích c?a CO càng cao thì ?? b?n g?y càng cao, nh?ng ?? c?ng và kh? n?ng ch?ng mài mòn càng th?p (Jia et al., 2007). Do ?ó, ?? có ???c hi?u su?t t?t h?n, thay vào ?ó, kh?ng th? tránh kh?i vi?c s? d?ng các v?t li?u xi m?ng khác.

M?t khác, vì nh?ng ly do trên, nó kh?ng khoa h?c trong chi?n l??c và d? ?nh h??ng ??n xu h??ng giá c?. Ngoài ra, s? k?t h?p gi?a WC và b?i ??ng là ?áng lo ng?i vì chúng gay ch?t ng??i nhi?u h?n b?t k? vi?c s? d?ng nào.

WC-Ni

Niken r? h?n và d? ki?m h?n coban. Nó có m?t tài s?n c?ng r?n t?t. Nó có th? ???c s? d?ng ?? c?i thi?n hi?u su?t ?n mòn / oxy hóa(chǎn), ?? b?n nhi?t ?? cao và ch?ng mài mòn trong m?i tr??ng kh?c nghi?t. So v?i h?p kim WC Co, ?? d?o c?a v?t li?u th?p h?n. B?i vì niken hòa tan t?t trong WC, nó ???c s? d?ng làm ch?t k?t dính cho ch?t n?n WC, d?n ??n liên k?t m?nh m? gi?a chúng.

WC-Ag

Vi?c b? sung Ag làm cho WC tr? thành m?t lo?i v?t li?u ch?ng h? quang. D??i tác ??ng c?a dòng quá t?i, WC th??ng ???c t?i trong các thi?t b? chuy?n m?ch, ?i?u này có th? ???c quy cho ?i?n tr? ti?p xúc ?i?n (RC) n?i ti?ng sau này. ?i?u ?áng nói là ?i?n tr? su?t c?a h?n h?p WC Ag gi?m khi t?ng hàm l??ng Ag và ?? c?ng gi?m khi t?ng hàm l??ng Ag, ?i?u này là do s? khác bi?t l?n gi?a ?? c?ng c?a WC và Ag. Ngoài ra, các h?t WC th? có s?c ?? kháng ti?p xúc r?t th?p và ?n ??nh.

Hình 13.4 cho th?y ?i?n tr? ti?p xúc ?i?n trung bình (RC) ???c t?o ra b?i c?ng t?c

Chu k? 11e50 v?i hàm l??ng b?c và kích th??c h?t WC khác nhau, b?i vì RC c?a h?u h?t các v?t li?u ???c quan sát là ?n ??nh sau 10 chu k? chuy?n ??i. ?i?n tr? ti?p xúc c?a b?c n?m trong kho?ng t? 50-55 wt% (t? l? th? tích 60% và 64.6%) trong WC v?i kích th??c h?t là 4 mm và t? 55-60 wt% (t? l? th? tích 64.6% và 69%) trong WC v?i kích th??c h?t 0,8 và 1,5 mm. Do ?ó, ?i?u này xác ??nh thành ph?n ban ??u c?a kho?n ??u t?, trong ?ó ma tr?n Ag ???c liên k?t hoàn toàn. ??i v?i các thành ph?n c? ??nh, s? gi?m ?i?n tr? ti?p xúc gi?a kích th??c h?t WC 1,5 ??n 4 mm ?? ???c quan sát, c?ng ?ánh d?u ng??ng th?m.

WC-Re

Các nhà khoa h?c ?ang s? d?ng cacbua vonfram ?? t?ng c??ng rheni ?? có ???c hi?u su?t t?t h?n WC Co, b?i vì RE có th? mang l?i ?? c?ng ? nhi?t ?? cao và s? k?t h?p t?t

Hình 13.4 t? l? c?a ?i?n tr? ti?p xúc ?i?n trung bình ? hàm l??ng Ag khác nhau và kích th??c h?t WC so v?i ?i?n tr? ti?p xúc c?a ch?t n?n WC trong chu k? 11 ??n 50 là co ho?c Ni. Theo ??c ?i?m c?u trúc vi m? c?a WC coere (hàm l??ng RE 20%), ???c m? t? r?ng WC coere gi? l?i trong CO và ti?p t?c hình thành c?u trúc HCP, do ?ó c?i thi?n ?? c?ng c?a h?p kim. Các nhà nghiên c?u c?ng t?ng c??ng l?i trong WC Ni và tìm th?y nh?ng suy lu?n t??ng t?. Do ?? c?ng cao nh?t và ?? b?n g?p ??i c?a WC Co, h?p kim ???c s? d?ng ?? s?n xu?t các b? ph?n c?ng c? c?nh tranh. Khi ép l?nh WC và b?t Re theo quy trình ép nóng ???c c?p b?ng sáng ch?, h?n 2400 kg / mm ~ 2 c?a HV ?? ???c quan sát (so v?i 1700 kg / mm ~ 2 ??i v?i WC-Co)

WC ??i x?ng

WC-FeAl

Trong vài th?p k? qua, các h?p ch?t intermetallic nh? ch?t k?t dính g?m ?? thu hút s? chú y c?a m?i ng??i. S?t aluminide có kh? n?ng ch?ng oxy hóa(chǎn) và ch?ng ?n mòn tuy?t v?i, ??c tính th?p, ?? c?ng cao, ch?ng mài mòn t?t, ?n ??nh nhi?t ?? cao và ?? ?m t?t. Nó là nhi?t ??ng phù h?p cho WC nh? ch?t k?t dính. ?? c?ng và ?? b?n g?y c?a WC FeAl và WC Co v? c? b?n là gi?ng nhau. ?? c?ng và kh? n?ng ch?ng mòn c?a h?p kim WC Co t??ng t? nh? h?p kim WC Co th?ng th??ng. Có th? xem xét r?ng n?u kích th??c h?t có th? ???c t?i ?u hóa(chǎn), có th? thay th? C?ng ty WC truy?n th?ng ???ng cong phan b? kích th??c h?t c?a b?t h?n h?p WC FeAl ???c ?i?u ch? b?ng các quá trình nghi?n và / ho?c s?y bóng khác nhau ???c th? hi?n trong Hình 13,5. Ba ???ng cong trong hình 13,5 có phan b? l??ng kim. Trong hình 13,5, ??nh trái c?a kích th??c h?t nh? h?n t??ng ?ng v?i ??nh trái c?a h?t WC ??n. Giá tr? ??nh chính xác c?a kích th??c h?t l?n h?n t??ng ?ng v?i giá tr? c?c ??i c?a các m?nh FeAl ch?a m?t s? h?t WC. Khi ??nh chính xác di chuy?n, ??nh trái kh?ng ph? thu?c vào quá trình nghi?n và / ho?c s?y. ??nh chính xác c?a b?t DR (ethanol ?? kh? n??c làm dung m?i ?? làm kh? nhanh) chuy?n sang ??nh t??ng ?ng c?a hai lo?i b?t còn l?i.

Hình 13,5 Phan b? kích th??c h?t c?a b?t h?n h?p WC-FeAl ???c ?i?u ch? t? các quy trình b?t khác nhau.

WC-g?m

WC-MgO

V?t li?u composite Wc-mgo ?? ???c s? d?ng r?ng r?i do vi?c b? sung các h?t MgO trong ma tr?n WC, ít ?nh h??ng ??n ?? c?ng và c?i thi?n ?áng k? ?? d?o dai c?a v?t li?u. ?? c?ng t? l? ngh?ch v?i ?? b?n, nh?ng trong tr??ng h?p c?a h?p kim này, ?? b?n có ???c khi ?? m?t ?? c?ng r?t nh?. Thêm m?t l??ng nh? VC, Cr3C2 và các ch?t ?c ch? t?ng tr??ng h?t khác vào v?t li?u ???c nghiên c?u kh?ng ch? có th? ki?m soát s? t?ng tr??ng c?a h?t trong quá trình thiêu k?t mà còn c?i thi?n tính ch?t c? h?c c?a v?t li?u.

WC-Al2O3

? ?ay ph?i ?? c?p r?ng Al 2 O 3 ???c s? d?ng làm v?t li?u gia c? cho WC và ng??c l?i, vì các tính ch?t c? ly tuy?t v?i c?a chúng.

Nhi?t ?? thiêu k?t và th?i gian gi? có ?nh h??ng ?áng k? ??n c?u trúc vi m? và tính ch?t c? h?c c?a h?n h?p wc-40vol% Al2O3. V?i s? gia t?ng c?a nhi?t ?? thiêu k?t và th?i gian gi?, m?t ?? t??ng ??i và kích th??c h?t t?ng lên. ??ng th?i, các giá tr? c?a áp l?c cao và ?? b?n g?y x??ng t?ng tr??c và sau ?ó gi?m. C?u trúc vi m? c?a ???ng n?t cho th?y s? t?n t?i c?a c?u n?t và ?? l?ch v?t n?t. Trong v?t li?u t?ng h?p wc-40vol% Al 2O 3, c? ch? làm c?ng chính là t?o ra các v?t n?t th? c?p và bên. M?t nghiên c?u khác cho th?y HV kho?ng 20e25gpa và ?? b?n g?y là 5e6mpa.m1 / 2.

Hình 13.6 cho th?y xu h??ng bi?n ??i c?a ?? c?ng, ?? b?n g?y và ?? b?n g?y ngang v?i hàm l??ng alumina. C?n l?u y r?ng nh?ng giá tr? này khá khác bi?t v?i nh?ng giá tr? ???c báo cáo (Mao et al., 2015). WC nguyên ch?t có ?? c?ng cao nh?t và ?? b?n g?y th?p nh?t. Vi?c b? sung Al2O3 giúp c?i thi?n ?? b?n g?y, nh?ng ?? c?ng c?a alumina tinh khi?t th?p h?n so v?i WC nguyên ch?t và ?? c?ng c?a composite wc-al2o3 gi?m. Các k?t qu? khác nhau trong Hình 13.6 cho th?y các tính ch?t c? h?c kh?ng ch? ph? thu?c vào hàm l??ng alumina, mà còn ph? thu?c vào quá trình s?n xu?t và c?p ch?t n?n khác nhau. 

WC mài mòn

WC cBN

Do CBN có ?? c?ng tuy?t v?i, ?? ?n ??nh nhi?t và ho?t ??ng ph?n ?ng v?i s?t, vi?c thêm CBN vào WC Co có th? c?i thi?n kh? n?ng ch?ng mài mòn, ?? c?ng và tính ch?t c? h?c c?a v?t li?u. Khi CBN ???c t?ng c??ng vào ma tr?n WC, ?? bám dính m?nh s? ???c t?o ra. Ngoài ra, ?? b?n g?y t?t h?n có th? ??t ???c b?ng cách làm l?ch v?t n?t ho?c b?c c?u c?a các h?t CBN. Hai tr? ng?i chính trong quá trình b? sung CBN là chuy?n ??i t? CBN sang hBN và liên k?t c?ng hóa(chǎn) tr? m?nh gi?a B và N, d?n ??n kh? n?ng thiêu k?t th?p c?a CBN và cacbua xi m?ng.

Kim c??ng WC

WC kim c??ng có ?? b?n g?y tuy?t v?i, ch?ng n?t t?ng tr??ng và ch?ng ph?n x?. V?t li?u này ch? có th? ???c s?n xu?t trong ?i?u ki?n nhi?t ??ng ?? ng?n kim c??ng bi?n thành than chì. Th?ng qua nhi?u nghiên c?u ?? c?i thi?n hi?u su?t c?a v?t li?u này, chúng t?i có th? t?o ra kho?ng cách chi phí r?t l?n, r?t c?n thi?t.

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Gi?i thi?u Thép ???c làm ngu?i b?ng cách nung nóng thép ??n nhi?t ?? cao h?n nhi?t ?? t?i h?n Ac3 (thép hypo-eutectoid) ho?c Ac1 (thép hypereutectoid), gi? nó trong m?t kho?ng th?i gian ?? austenit hóa(chǎn) toàn b? ho?c m?t ph?n, sau ?ó ???c làm ngu?i ? nhi?t ?? nhi?t ?? l?n h?n t?c ?? làm ngu?i t?i h?n Làm l?nh nhanh xu?ng d??i Ms (ho?c Ms g?n ??ng nhi?t) quá trình x? ly nhi?t martensitic (ho?c bainite). X? ly dung d?ch các v?t li?u nh? h?p kim nh?m, h?p kim ??ng, h?p kim titan, kính c??ng l?c, v.v., ho?c các quá trình x? ly nhi?t v?i làm l?nh nhanh c?ng th??ng ???c g?i là quá trình t?i. Làm ngu?i là m?t quá trình x? ly nhi?t ph? bi?n, ch? y?u ???c s? d?ng ?? t?ng ?? c?ng c?a v?t li?u. Th?ng th??ng t? m?i tr??ng làm ngu?i, có th? ???c chia thành làm ngu?i b?ng n??c, làm ngu?i d?u, làm ngu?i h?u c?. V?i s? phát tri?n c?a khoa h?c và c?ng ngh?, m?t s? quy trình d?p t?t m?i ?? xu?t hi?n.1 Ph??ng pháp d?p t?t làm mát b?ng kh?ng khí áp su?t cao Các ph?i trong dòng khí tr? m?nh ???c làm mát nhanh chóng và ??ng ??u, ?? ng?n ch?n quá trình oxy hóa(chǎn) b? m?t, tránh n?t, gi?m bi?n d?ng, ?? ??m b?o r?ng ?? c?ng c?n thi?t, ch? y?u ?? làm ngu?i thép c?ng c?. C?ng ngh? này g?n ?ay ?? phát tri?n nhanh chóng và ph?m vi ?ng d?ng c?ng ?? ???c m? r?ng ?áng k?. Hi?n t?i, c?ng ngh? làm ngu?i khí chan kh?ng ?? phát tri?n nhanh chóng và làm mát khí t?c ?? dòng ch?y cao áp su?t am (<1 × 105 Pa), sau ?ó là làm mát khí và áp su?t cao (1 × 105 ~ 4 × 105 Pa) 10 × 105 Pa) kh?ng khí -làm mát, làm mát b?ng kh?ng khí áp su?t c?c cao (10 × 105 ~ 20 × 105 Pa) và các c?ng ngh? m?i khác kh?ng ch? giúp t?ng c??ng ?áng k? kh? n?ng làm ngu?i chan kh?ng c?a làm mát b?ng kh?ng khí mà còn làm ngu?i ?? sáng b? m?t ph?i t?t, bi?n d?ng nh?, nh?ng c?ng có hi?u qu? cao, ti?t ki?m n?ng l??ng, kh?ng gay ? nhi?m, v.v. Vi?c s? d?ng ph??ng pháp làm ngu?i b?ng khí làm mát b?ng khí áp su?t cao chan kh?ng là quá trình làm ngu?i và t?i luy?n v?t li?u, dung d?ch, quá trình l?o hóa(chǎn), cacbon hóa(chǎn) ion và th?m cacbon c?a thép kh?ng g? và các h?p kim ??c bi?t, c?ng nh? quá trình thiêu k?t chan kh?ng, làm mát và làm ngu?i sau khi hàn. V?i quá trình làm ngu?i b?ng nit? áp su?t cao 6 × 105 Pa, t?i ch? có th? ???c làm mát r?i, thép t?c ?? cao (W6Mo5Cr4V2) có th? ???c làm c?ng ??n 70 ~ 100 mm, thép ch?t gia c?ng h?p kim cao lên ??n 25 ~ 100 mm, vàng l?nh thép khu?n làm vi?c (ch?ng h?n nh? Cr12) lên ??n 80 ~ 100 mm. Khi ???c làm ngu?i b?ng nit? áp su?t cao 10 × 10 5 Pa, t?i ???c làm mát có th? r?t m?nh, làm t?ng m?t ?? t?i kho?ng 30% lên 40% so v?i làm mát b?ng 6 × 10 5 Pa. Khi ???c làm ngu?i b?ng nit? c?c cao 20 × 10 5 Pa. nit? áp su?t ho?c h?n h?p helium và nit?, các t?i ???c làm mát s? dày ??c và có th? ???c bó l?i v?i nhau. M?t ?? làm mát b?ng nit? 6 × 105 Pa 80% ??n 150%, có th? làm mát t?t c? thép t?c ?? cao, thép h?p kim cao, thép c?ng c? gia c?ng nóng và thép crom Cr13% và nhi?u lo?i thép t?i d?u h?p kim h?n, ch?ng h?n nh? thép 9Mn2V kích th??c l?n h?n. Lò t?i hai bu?ng làm mát b?ng kh?ng khí v?i các bu?ng làm mát riêng bi?t có kh? n?ng làm mát t?t h?n so v?i các lo?i lò m?t bu?ng cùng lo?i. Lò ??i bu?ng làm mát b?ng nit? 2 × 105 Pa có hi?u qu? làm mát t??ng t? nh? lò bu?ng ??n 4 × 105 Pa. Tuy nhiên, chi phí v?n hành, chi phí b?o trì th?p. Khi ngành c?ng nghi?p v?t li?u c? b?n c?a Trung Qu?c (than chì, molypden, v.v.) và các thành ph?n ph? tr? (??ng c?) và các c?p ?? khác ???c c?i thi?n. Do ?ó, ?? c?i thi?n vi?c ch?m sóc chan kh?ng áp su?t cao m?t bu?ng 6 × 105 Pa trong khi duy trì s? phát tri?n c?a lò làm ngu?i áp su?t bu?ng kép và làm mát b?ng kh?ng khí áp su?t cao phù h?p h?n v?i ?i?u ki?n qu?c gia c?a Trung Qu?c. Hình 1 kh?ng khí áp su?t cao- lò chan kh?ng làm mát2 ph??ng pháp làm ngu?i m?nh Ph??ng pháp làm ngu?i th?ng th??ng th??ng là làm mát b?ng d?u, n??c ho?c dung d?ch polyme, và quy t?c làm ngu?i m?nh b?ng n??c ho?c n??c mu?i n?ng ?? th?p. Làm ngu?i m?nh ???c ??c tr?ng b?i kh? n?ng làm ngu?i c?c nhanh, mà kh?ng ph?i lo l?ng v? s? bi?n d?ng quá m?c c?a thép và n?t. Quá trình làm ngu?i th?ng th??ng ??n nhi?t ?? làm ngu?i, s?c c?ng b? m?t thép ho?c tr?ng thái ?ng su?t th?p, và làm ngu?i m?nh ? gi?a quá trình làm mát, tam ph?i v?n ? tr?ng thái nóng ?? ng?ng làm mát, do ?ó hình thành ?ng su?t nén b? m?t. Trong ?i?u ki?n làm ngu?i kh?c nghi?t, austenite siêu l?nh trên b? m?t thép ph?i ch?u ?ng su?t nén 1200 MPa khi t?c ?? làm mát c?a vùng bi?n ??i martensitic cao h?n 30 ℃ / s, do ?ó c??ng ?? n?ng su?t c?a thép sau khi làm ngu?i ???c t?ng ít nh?t là 25%.Nguyên ly: Thép t? quá trình t?i ? nhi?t ?? austenit hóa(chǎn), chênh l?ch nhi?t ?? gi?a b? m?t và tim s? d?n ??n ?ng su?t bên trong. S? thay ??i pha c?a th? tích riêng c?a ch?t thay ??i pha và d?o thay ??i pha c?ng s? gay ra ?ng su?t chuy?n pha b? sung. N?u ?ng su?t nhi?t và ?ng su?t chuy?n pha ch?ng ch?t, t?c là ?ng su?t t?ng th? v??t quá c??ng ?? n?ng su?t c?a v?t li?u thì s? x?y ra bi?n d?ng d?o; n?u ?ng su?t v??t quá ?? b?n kéo c?a thép nóng s? hình thành v?t n?t d?p t?t. Trong quá trình làm ngu?i c??ng ?? cao, ?ng su?t d? do ?? d?o thay ??i pha gay ra và ?ng su?t d? t?ng do s? thay ??i th? tích riêng c?a quá trình bi?n ??i austenite-martensite. Trong quá trình làm mát c??ng ?? cao, b? m?t ph?i ngay l?p t?c ???c làm mát ??n nhi?t ?? b?, nhi?t ?? tim h?u nh? kh?ng thay ??i. Làm l?nh nhanh gay ra ?ng su?t kéo cao làm co l?p b? m?t và ???c can b?ng b?i ?ng su?t tim. S? gia t?ng c?a gradient nhi?t ?? làm t?ng ?ng su?t kéo do quá trình bi?n ??i mactenxit ban ??u gay ra, trong khi s? gia t?ng nhi?t ?? b?t ??u bi?n ??i mactenxit Ms s? làm cho l?p b? m?t gi?n n? do tính d?o chuy?n pha, ?ng su?t kéo b? m?t s? gi?m và bi?n ??i ?áng k? thành ?ng su?t nén, ?ng su?t nén b? m?t t? l? v?i l??ng mactenxit b? m?t sinh ra. ?ng su?t nén b? m?t này xác ??nh li?u tim có tr?i qua quá trình bi?n ??i martensitic trong ?i?u ki?n nén hay khi làm mát thêm, s? ??o ng??c ?ng su?t kéo b? m?t. N?u s? bi?n ??i mactenxit c?a s? gi?n n? th? tích tim ?? l?n, và mactenxit b? m?t r?t c?ng và giòn, nó s? làm cho l?p b? m?t b? v? do ?ng su?t ??o chi?u. ?? ??t ???c ?i?u này, b? m?t thép ph?i xu?t hi?n ?ng su?t nén và quá trình bi?n ??i martensitic ? tim ph?i x?y ra càng mu?n càng t?t. Th? nghi?m t?i luy?n m?nh và hi?u su?t t?i luy?n thép: Ph??ng pháp t?i luy?n m?nh có ?u ?i?m là hình thành ?ng su?t nén trên b? m?t, gi?m nguy c? n?t và c?i thi?n ?? c?ng và s?c m?nh. S? hình thành b? m?t c?a martensite 100%, thép s? có l?p c?ng l?n nh?t, nó có th? thay th? thép cacbon ??t ti?n h?n, t?i m?nh c?ng có th? thúc ??y các tính ch?t c? h?c ??ng nh?t c?a thép và t?o ra ?? bi?n d?ng nh? nh?t c?a ph?i. Các b? ph?n sau khi làm ngu?i, tu?i th? c?a d?ch v? d??i t?i tr?ng xen k? có th? t?ng lên theo m?t m?c ?? l?n. [1]Hình 2 xác su?t hình thành v?t n?t d?p t?t m?nh và m?i quan h? t?c ?? làm mát3 ph??ng pháp làm mát h?n h?p n??c-kh?ng khíB?ng cách ?i?u ch?nh áp su?t c?a n??c và kh?ng khí và kho?ng cách gi?a vòi phun nguyên t? và b? m?t ph?i, kh? n?ng làm mát c?a h?n h?p n??c-kh?ng khí có th? thay ??i và làm mát có th? ??ng ??u. Th?c ti?n s?n xu?t cho th?y r?ng vi?c s? d?ng quy lu?t v? hình d?ng c?a các b? ph?n làm c?ng b? m?t b?ng thép carbon ho?c thép h?p kim ph?c t?p, có th? ng?n ch?n hi?u qu? vi?c t?o ra các v?t n?t làm ngu?i. , có th? có tác d?ng làm c?ng t?t h?n, ?? làm ngu?i ho?c bình th??ng hóa(chǎn) thép. Hi?n t?i, c?ng ngh? này ?? ???c áp d?ng thành c?ng ?? t?i gang d?o. L?y h?p kim nh?m làm ví d?: Theo các th?ng s? k? thu?t x? ly nhi?t hi?n t?i ??i v?i rèn và rèn h?p kim nh?m, nhi?t ?? n??c t?i th??ng ???c ki?m soát d??i 60 ° C, nhi?t ?? n??c t?i th?p, t?c ?? làm mát cao và d? l??ng l?n c?ng th?ng sau khi d?p t?t x?y ra. Trong quá trình gia c?ng cu?i cùng, ?ng su?t bên trong m?t can b?ng do hình d?ng và kích th??c b? m?t kh?ng ??ng nh?t, d?n ??n gi?i phóng ?ng su?t d?, d?n ??n các ph?n b? bi?n d?ng, u?n cong, hình b?u d?c và các ph?n bi?n d?ng khác c?a b? ph?n gia c?ng tr? thành ch?t th?i cu?i cùng kh?ng th? ph?c h?i v?i t?n th?t nghiêm tr?ng. Ví d?: cánh qu?t, cánh máy nén và các bi?n d?ng rèn h?p kim nh?m khác sau khi gia c?ng r? ràng, d?n ??n dung sai kích th??c các b? ph?n. Nhi?t ?? n??c t?i t?ng t? nhi?t ?? phòng (30-40 ℃) lên nhi?t ?? n??c s?i (90-100 ℃), ?ng su?t d? rèn trung bình gi?m kho?ng 50%. [2]Hình 4 S? ?? làm ngu?i b?ng n??c s?i5 Ph??ng pháp làm ngu?i b?ng d?u nóng Vi?c s? d?ng d?u làm ngu?i nóng ?? ph?i tr??c khi làm ngu?i thêm ? nhi?t ?? b?ng ho?c g?n v?i nhi?t ?? c?a ?i?m Ms ?? gi?m thi?u chênh l?ch nhi?t ??, có th? ng?n ch?n quá trình làm ngu?i m?t cách hi?u qu? s? bi?n d?ng ph?i và n?t. Kích th??c nh? c?a thép c?ng c? h?p kim ch?t ngu?i 160 ~ 200 ℃ trong quá trình làm ngu?i d?u nóng, có th? làm gi?m bi?n d?ng và tránh n?t m?t cách hi?u qu?. austenite ???c gi? l?i ti?p t?c ???c chuy?n thành martensite, m?c ?ích là c?i thi?n ?? c?ng và kh? n?ng ch?ng mài mòn c?a thép, c?i thi?n ?? ?n ??nh c?u trúc và ?? ?n ??nh kích th??c c?a ph?i, ??ng th?i c?i thi?n hi?u qu? tu?i th? c?a d?ng c?. X? ly ??ng l?nh là nit? l?ng nh? m?t ph??ng ti?n làm mát cho các ph??ng pháp x? ly v?t li?u. C?ng ngh? x? ly ??ng l?nh l?n ??u tiên ???c áp d?ng cho các d?ng c? mài mòn, v?t li?u d?ng c? khu?n, sau ?ó ???c m? r?ng sang thép h?p kim, cacbua, v.v., s? d?ng ph??ng pháp này có th? thay ??i c?u trúc bên trong c?a v?t li?u kim lo?i, t? ?ó c?i thi?n tính ch?t c? h?c và tính ch?t gia c?ng, ?ó là hi?n t?i M?t trong nh?ng quy trình c??ng l?c m?i nh?t. X? ly ??ng l?nh (X? ly ??ng l?nh), còn ???c g?i là x? ly nhi?t ?? c?c th?p, th??ng ?? c?p ??n v?t li?u d??i -130 ℃ ?? x? ly nh?m c?i thi?n hi?u su?t t?ng th? c?a v?t li?u. Ngay t? 100 n?m tr??c, ng??i ta ?? b?t ??u x? ly l?nh áp d?ng cho các b? ph?n c?a ??ng h?, giúp c?i thi?n ?? b?n, kh? n?ng ch?ng mài mòn, ?n ??nh kích th??c và tu?i th?. X? ly ??ng l?nh là m?t c?ng ngh? m?i ???c phát tri?n trên c? s? x? ly l?nh th?ng th??ng vào nh?ng n?m 1960. So v?i x? ly l?nh th?ng th??ng, x? ly ??ng l?nh có th? c?i thi?n h?n n?a các tính ch?t c? h?c và ?? ?n ??nh c?a v?t li?u, ??ng th?i có tri?n v?ng ?ng d?ng r?ng h?n. C? ch? x? ly ??ng l?nh: Sau khi x? ly ??ng l?nh, austenite còn l?i trong c?u trúc bên trong c?a v?t li?u kim lo?i (ch? y?u là khu?n v?t li?u) ???c chuy?n thành martensite, và cacbua k?t t?a c?ng ???c k?t t?a trong martensite, do ?ó có th? lo?i b? martensite trong ?ng su?t d?, nh?ng c?ng t?ng c??ng ma tr?n martensite, do ?ó ?? c?ng và kh? n?ng ch?ng mài mòn c?a nó c?ng s? t?ng lên. S? d? ?? c?ng t?ng lên là do s? bi?n ??i m?t ph?n austenit gi? l?i thành mactenxit. S? gia t?ng ?? d?o dai là do s? phan tán và k?t t?a η-Fe3C nh?. ??ng th?i, hàm l??ng carbon c?a martensite gi?m và ?? bi?n d?ng m?ng gi?m, C?i thi?n ?? d?o. Thi?t b? x? ly ??ng l?nh ch? y?u bao g?m b? ch?a nit? l?ng, h? th?ng truy?n nit? l?ng, h?p l?nh sau và h? th?ng ?i?u khi?n. Trong ?ng d?ng, x? ly ??ng l?nh ???c l?p l?i nhi?u l?n. Các quy trình ?i?n hình nh?: t?i d?u 1120 ℃ + -196 ℃ × 1h (2-4) x? ly ??ng l?nh sau + ? 200 ℃ × 2h. Sau khi x? ly t? ch?c, ?? có s? bi?n ??i c?a austenite, nh?ng c?ng ???c k?t t?a t? s? phan tán martensite ?? ???c làm ngu?i có m?i quan h? ch?t ch? cao v?i ma tr?n cacbua siêu m?n, sau khi ? ? nhi?t ?? th?p ti?p theo ? 200 ℃, s? phát tri?n c?a cacbua siêu m?n Phan tán ε cacbua , s? l??ng và ?? phan tán t?ng lên ?áng k?. Vi?c x? ly ??ng l?nh ???c l?p ?i l?p l?i m?t s? l?n. M?t m?t, các cacbua siêu m?n ???c k?t t?a t? martensite ???c bi?n ??i t? austenite ???c gi? l?i t?i th?i ?i?m làm l?nh b?ng ph??ng pháp ??ng l?nh tr??c ?ó. M?t khác, các cacbua m?n ti?p t?c ???c k?t t?a trong mactenxit ?? t?i. Quá trình l?p ?i l?p l?i có th? làm t?ng c??ng ?? nén ma tr?n, c??ng ?? n?ng su?t và ?? b?n va ??p, c?i thi?n ?? d?o dai c?a thép, ??ng th?i làm cho kh? n?ng ch?ng mài mòn do va ??p ???c c?i thi?n ?áng k?. x? ly do ?ng su?t nhi?t gay ra b?i bi?n d?ng quá m?c, t?c ?? làm mát ph?i ???c ki?m soát trong quá trình x? ly b?ng ph??ng pháp ??ng l?nh. Ngoài ra, ?? ??m b?o tính ??ng nh?t c?a tr??ng nhi?t ?? bên trong thi?t b? và gi?m dao ??ng nhi?t ??, thi?t k? c?a h? th?ng x? ly ??ng l?nh c?n tính ??n ?? chính xác ki?m soát nhi?t ?? c?a h? th?ng và tính h?p ly c?a vi?c b? trí tr??ng dòng ch?y. Trong thi?t k? h? th?ng c?ng nên chú y ?áp ?ng tiêu th? ít n?ng l??ng, hi?u qu? cao, v?n hành d? dàng và các yêu c?u khác. ?ay là xu h??ng phát tri?n hi?n nay c?a h? th?ng x? ly ??ng l?nh. Ngoài ra, m?t s? h? th?ng làm l?nh ?ang phát tri?n có nhi?t ?? làm l?nh kéo dài t? nhi?t ?? phòng ??n nhi?t ?? th?p c?ng ???c d? ki?n s? phát tri?n thành h? th?ng x? ly ??ng l?nh kh?ng ch?a ch?t l?ng v?i vi?c gi?m nhi?t ?? t?i thi?u và c?i thi?n hi?u qu? làm l?nh. [3]Tài li?u tham kh?o:[1]樊東黎.強(qiáng)烈淬火——一種新的強(qiáng)化鋼的熱處理方法[J].熱處理, 2005, 20(4): 1-3[2]宋微, 郝冬梅, 王成江.沸水淬火對鋁合金鍛件組織與機(jī)械性能的影響[J].鋁加工, 2002, 25(2): 1-3[3]夏雨亮, 金滔, 湯珂.深冷處理工藝及設(shè)備的發(fā)展現(xiàn)狀和展望[J].低溫與特氣, 2007, 25(1): 1-3
Ngu?n: Meeyou cacbua

First, the molecular beam epitaxial profileIn the ultra-high vacuum environment, with a certain thermal energy of one or more molecules (atoms) beam jet to the crystal substrate, the substrate surface reaction processMolecules in the “flight” process almost no collision with the ambient gas, in the form of molecular beam to the substrate, the epitaxial growth, hence the name.Properties: A vacuum deposition methodOrigin: 20th century, the early 70s, the United States Bell laboratoryApplications: epitaxial growth atomic level precise control of ultra-thin multi-layer two-dimensional structure materials and devices (super-character, quantum wells, modulation doping heterojunction, quantum yin: lasers, high electron mobility transistors, etc.); combined with other processes, But also the preparation of one-dimensional and zero-dimensional nano-materials (quantum lines, quantum dots, etc.).Typical features of MBE:(1) The molecules (atoms) emitted from the source furnace reach the substrate surface in the form of a “molecular beam” stream. Through the quartz crystal film thickness monitoring, can strictly control the growth rate.(2) molecular beam epitaxy growth rate is slow, about 0.01-1nm / s. Can achieve single atomic (molecular) layer epitaxy, with excellent film thickness controllability.(3) By adjusting the opening and closing of the baffle between the source and the substrate, the composition and the impurity concentration of the film can be strictly controlled, and selective epitaxial growth can be achieved.(4) non-thermal equilibrium growth, the substrate temperature can be lower than the equilibrium temperature, to achieve low temperature growth, can effectively reduce the interdiffusion and self-doping.(5) with reflective high-energy electron diffraction (RHEED) and other devices, can achieve the original price observation, real-time monitoring.Growth rate is relatively slow, both MBE is an advantage, but also its lack, not suitable for thick film growth and mass production.Second, silicon molecular beam epitaxy1 basic profileSilicon molecular beam epitaxy includes homogeneous epitaxy, heteroepitaxy.The silicon molecular beam epitaxy is the epitaxial growth of silicon (or silicon-related materials) on a suitably heated silicon substrate by physical deposition of atoms, molecules or ions.(1) during the epitaxial period, the substrate is at a lower temperature.(2) Simultaneous doping.(3) the system to maintain high vacuum.(4) pay special attention to the atomic clean surface.Figure 1 Schematic diagram of the working principle of silicon MBE2 Development history of silicon molecular beam epitaxyDeveloped relative to CVD defects.CVD defects: substrate high temperature, 1050oC, to the doping serious (with high temperature). The original molecular beam epitaxy: the silicon substrate heated to the appropriate temperature, vacuum evaporation of silicon to the silicon substrate, the epitaxial growth.Growth Criteria: The incident molecules move sufficiently to the hot surface of the substrate and are arranged in the form of a single crystal.3 The importance of silicon molecular beam epitaxyThe silicon MBE is carried out in a strictly controlled cryogenic system.(1) can well control the impurity concentration to reach the atomic level. The undoped concentration is controlled at <3 × 1013 / cm3.(2) The epitaxy can be carried out under the best conditions without defects.(3) The thickness of the epitaxial layer can be controlled within the thickness of the single atomic layer, superlattice epitaxy, several nm ~ several tens of nm, which can be designed manually, and the preparation of excellent performance of the new functional materials.(4) Homogeneous epitaxy of silicon, heteroepitaxy of silicon.4 epitaxial growth equipmentDevelopment direction: reliability, high performance and versatilityDisadvantages: high prices, complex, high operating costs.Scope: can be used for silicon MBE, compound MBE, III-V MBE, metal semiconductor MBE is developing.Basic common features:(1) basic ultra-high vacuum system, epitaxial chamber, Nuosen heating room;(2) analysis means, LEED, SIMS, Yang EED, etc .;(3) injection chamber.Figure 2 Schematic diagram of silicon molecular beam epitaxial system(1) electron beam bombardment of the surface of the silicon target, making it easy to produce silicon molecular beam. In order to avoid the radiation of the silicon molecular beam to the side to cause adverse effects, large area screen shielding and collimation is necessary.(2) resistance to heating the silicon cathode can not produce strong molecular beam, the other graphite citrus pots have Si-C stained, the best way is to electron beam evaporation to produce silicon source. Because, some parts of the silicon MBE temperature is higher, easy to evaporate, silicon low evaporation pressure requirements of the evaporation source has a higher temperature. At the same time, the beam density and scanning parameters to control. Making the silicon melting pit just in the silicon rod, silicon rods become high-purity citrus.There are several kinds of monitoring molecular beam:(1) Quartz crystal is often used to monitor beam current, beam shielding and cooling appropriate, can be satisfied with the results, but the noise affects the stability. After several μm, the quartz crystal loses its linearity. Frequent exchange, the main system is often inflated, which is not conducive to work.(2) small ion table, measured molecular beam pressure, rather than measuring the molecular beam flux. Due to the deposition on the system components leaving the standard.(3) low-energy electron beam, through the molecular beam, the use of electrons detected by the excitation fluorescence. The atoms are excited and quickly degrade to the ground state to produce uv fluorescence, and the optical density is proportional to the beam density after optical focusing. Do the feedback control of the silicon source. Inadequate: cut off the electron beam, most of the infrared fluorescence and background radiation will make the signal to noise ratio deteriorated to the extent of instability. It only measured atomic class, can not measure molecular substances.(4) Atomic absorption spectra, monitoring the beam density of doped atoms.With the intermittent beam current, Si and Ga were detected by 251.6nm and 294.4nm optical radiation respectively. The absorption intensity of the beam through the atomic beam was converted into atomic beam density and the corresponding ratio was obtained.Molecular beam epitaxy (MBE) substrate base is a difficult point.MBE is a cold wall process, that is, silicon substrate heating up to 1200 ℃, the environment to room temperature. In addition, the silicon wafer to ensure uniform temperature. Hill resistance refractory metal and graphite cathode, the back of the radiation heating, and the entire heating parts are installed in liquid nitrogen cooled containers, in order to reduce the thermal radiation of the vacuum components. The substrate is rotated to ensure uniform heating. Free deflection, can enhance the secondary implantation doping effect.
Ngu?n: Meeyou cacbua

1, Review of Organic Halide Perovskite – related Photoelectric PropertiesFigure 1 Spectral position and PL peakOrganic halide perovskites are widely used in optoelectronics research. Methyl ammonium and formamidine lead iodide as photovoltaics show excellent photoelectric properties and stimulate researchers’ enthusiasm for light-emitting devices and photodetectors. Recently, the University of Toronto Edward H. Sargent (Correspondent) team of organic metal halide perovskite optical and electrical properties of the material were studied. Outlines how material composition and form are associated with these attributes, and how these properties ultimately affect device performance. In addition, the team also analyzed different material properties of the perovskite materials, in particular the bandgap, mobility, diffusion length, carrier lifetime and trap density.The Electrical and Optical Properties of Organometal Halide Perovskites Relevant to Optoelectronic Performance（Adv.Mater.,2017,DOI: 10.1002/adma.201700764）2, Advanced Materials Overview: 2D optoelectronic applications of organic materials Figure 2 Several key steps in the application of two-dimensional organic materialsThe 2D material with atomic thin structure and photoelectron properties has attracted the interest of researchers in applying 2D materials to electronics and optoelectronics. In addition, as a two-dimensional material series of emerging areas, the organic nanostructure assembled into 2D form provides molecular diversity, flexibility, ease of processing, light weight, etc., for optoelectronic applications provides an exciting prospect. Recently, Tianjin University, Professor Hu Wenping, Ren Xiaochen assistant researcher (common newsletter) and others reviewed the application of organic two-dimensional materials in optoelectronic devices. Examples of materials include 2D, organic, crystalline, small molecules, polymers, self- Covalent organic skeleton. The application of 2D organic crystal fabrication and patterning technology is also discussed. Then the application of optoelectronic devices is introduced in detail, and the prospect of 2D material is briefly discussed.2D Organic Materials for Optoelectronic Applications（Adv.Mater.,2017,DOI: 10.1002/adma.201702415）3, Advanced Materials Review: 2D Ruddlesden-Popper Perovskite PhotonicsFigure 3 Schematic diagram of 3D and 2D perovskite structuresThe traditional 3D organic-inorganic halide perovskite has recently undergone unprecedented rapid development. However, their inherent instabilities in moisture, light and calories remain a key challenge before commercialization. In contrast, the emerging two-dimensional Ruddlesden-Popper perovskite has received increasing attention due to its environmental stability. However, 2D perovskite research has just started. Recently, the University of Fudan University, Liang Ziqi (Corresponding author) team published a review first introduced 2D perovskite and 3D control of a detailed comparison. And then discussed the two-dimensional perovskite organic interval cationic engineering. Next, quasi-two-dimensional perovskites between 3D and 2D perovskites were studied and compared. In addition, 2D perovskite unique exciton properties, electron-phonon coupling and polaron are also shown. Finally, a reasonable summary of the structure design, growth control and photophysics research of 2D perovskite in high performance electronic devices is presented.2D Ruddlesden–Popper Perovskites for Optoelectronics（Adv.Mater.,2017,DOI: 10.1002/adma.201703487）4, Science Advances Summary: Lead Halide Perovskite: Crystal-Liquid Binary, Phonon Glass Electronic Crystals and Great Polaron FormationFigure 4 CH3NH3PbX3 perovskite structureLead anodized perovskite has proven to be a high performance material in solar cells and light emitting devices. These materials are characterized by the expected coherent band transport of crystalline semiconductors, as well as the dielectric response and phonon dynamics of the liquid. This “crystal-liquid” duality means that lead halide perovskites belong to phonon glass electron crystals – a class of thermoelectric materials that are considered to be the most efficient. Recently, the University of Columbia Zhu Xiaoyang (communication author) team reviewed the crystal-liquid duality, the resulting dielectric response responsible for the formation and selection of carrier polaron, which causes perovskite with defect tolerance, moderate Of the carrier mobility and the combined performance of the radiation. Large polaron formation and phonon glass characteristics can also explain the significant reduction in carrier cooling rates in these materials.Lead halide perovskites: Crystal-liquid duality, phonon glass electron crystals, and large polaron formation（Sci. Adv.,2017,DOI:10.1126/sciadv.1701469）5, Progress in Polymer Science Review: Lithography of silicon-containing block copolymersFig.5 Melt phase diagram of diblock copolymerRecently, the National Tsinghua University Rong-Ming Ho (Correspondent) and others published a summary of the different methods through the preparation of ordered block copolymer (BCP) film the latest progress, focusing on the use of silicon-containing BCP as lithography applications. With the advantages of Si-containing blocks, these BCPs have smaller feature sizes due to their high resolution, large segregation intensity and high etch contrast. Considering that poly (dimethylsiloxane) (PDMS) has been extensively studied in Si-containing BCPs, the possibility of photolithography using PDCP-containing BCP has been demonstrated through previous and ongoing studies. Subsequent sections detail the main results of the DSA approach. The new trend of lithographic printing application and the application of photolithography nano – pattern using silicon – containing BCPs are also discussed. Finally, the conclusion and prospect of BCP lithography are introduced.Silicon-Containing Block Copolymers for Lithographic Applications（Prog. Polym. Sci.,2017,DOI:10.1016/j.progpolymsci.2017.10.002）6, Angewandte Chemie International Edition Overview: CH3NH3PbI3 perovskite solar cell theoretical studyFigure 6 Electronic density patternPower conversion efficiency (PCEs) of more than 22% of the hybridized perovskite perovskite solar cells (PSCs) has attracted considerable attention. Although perovskite plays an important role in the operation of PSCs, the basic theory associated with perovskite remains unresolved. Recently, Professor Xun Nining (Communication Author) of Xi’an University of Architecture and Technology, according to the first principle, evaluated the existing theory of structure and electronic properties, defects, ion diffusion and transfer current of CH3NH3PbI3 perovskite, and ion transport Influence on PSC Current – Voltage Curve Hysteresis. The moving current associated with the possible ferroelectricity is also discussed. And emphasizes the benefits, challenges and potential of perovskite for PSCs.Theoretical Treatment of CH3NH3PbI3 Perovskite Solar Cells（Angew. Chem. Int. Ed.,2017,DOI: 10.1002/anie.201702660）7, Chemical Society Reviews Overview: Reductive Batteries for Electromechanical Active Materials for Molecular EngineeringFigure 7 Molecular engineering for redox substances for sustainable RFBAs an important large energy storage system, redox batteries (RFBs) have high scalability and independent energy and power control capabilities. However, conventional RFB applications are subject to performance and limitations on high cost and environmental issues associated with the use of metal-based redox substances. Recently, the University of Texas at Austin Guihua Yu (communication author) team proposed the design of these new redox substances system molecular engineering program. The article provides a detailed synthesis strategy for modifying organometallic and organometallic redox substances in terms of solubility, oxidation-reduction potential and molecular size. And then introduced recent advances covering the reaction mechanism of the redox species classified by its molecular structure, the specific functionalization methods and electrochemical properties. Finally, the author analyzes the future development direction and challenge of this emerging research field.Molecular engineering of organic electroactive materials for redox flow batteries （Chem.Soc.Rev.,2017,DOI: 10.1039/C7CS00569E）8, Chemical Society Reviews Overview: Atomic level for energy storage and conversion Non-layered nanomaterialsFigure 8 Atomic-grade layered and non-layered nanomaterialsSince the discovery of graphene, the two-dimensional nanomaterials with large atomic thickness and large lateral dimension are highly studied because of their high specific surface area, heterogeneous electronic structure and attractive physical and chemical properties. Recently, Wulonggong University Dushi University academician (communication author) team comprehensively summed up the atomic thickness of non-layered nano-materials preparation method, studied its heterogeneous electronic structure, the introduction of electronic structure operation strategy, and outlined its energy storage and conversion Applications, with particular emphasis on lithium-ion batteries, sodium ion batteries, oxygen, CO2 reduction, CO oxidation reaction. Finally, based on the current research progress, put forward the future direction – in practical application to enhance the performance and new features to explore.Atomically thin non-layered nanomaterials for energy storage and conversion （Chem.Soc.Rev.,2017,DOI:10.1039/C7CS00418D）9, Chemical Reviews Overview: Electrochemical Applications in the Synthesis of Heterocyclic StructuresFigure 9 Mechanism of electro-induced cationic chain reactionThe heterocycle is one of the largest organic compounds to date, and the preparation and transformation of heterocyclic structures have been of great interest to organic chemistry researchers. Various heterocyclic structures are widely found in biologically active natural products, organic materials, agrochemicals and drugs. When people notice that about 70% of all drugs and agrochemicals have at least one heterocycle, people can not ignore them importance. Recently, Professor Zeng Chengchao of Beijing University of Technology (Correspondent Author) team reviewed the progress of electrochemical construction of heterocyclic compounds published by intramolecular and intermolecular cyclization since 2000.Use of Electrochemistry in the Synthesis of Heterocyclic Structures（Chem. Rev.,2017,DOI:10.1021/acs.chemrev.7b00271）
Ngu?n: Meeyou cacbua

First, the development of a brief historyThe first stage: 1945 to 1951, the invention of nuclear magnetic resonance and lay the theoretical and experimental basis of the period: Bloch (Stanford University, observed in the water proton signal) and Purcell (Harvard University, observed in the paraffin proton signal) obtained Nobel bonus.The second stage: 1951 to 1960 for the development period, its role by chemists and biologists recognized, to solve many important problems. 1953 appeared in the first 30MHz nuclear magnetic resonance spectrometer; 1958 and early in the emergence of 60MHz, 100MHz instrument. In the mid-1950s, 1H-NMR, 19F-NMR and 31P-NMR were developed.The third stage: 60 to 70 years, NMR technology leap period. Pulse Fourier transform technology to improve the sensitivity and resolution, can be routinely measured 13C nuclear; dual frequency and multi frequency resonance technology;The fourth stage: the late 1970s theory and technology development mature.1,200, 300, 500 MHz and 600 MHz superconducting NMR spectrometers;2, the application of a variety of pulse series, in the application made important development;3, 2D-NMR appeared;4, multi-core research, can be applied to all magnetic cores;5, there have been “nuclear magnetic resonance imaging technology” and other new branch disciplines.Second, the main purpose:1. Determination and confirmation of the structure, and sometimes can determine the configuration, conformation2. Compound purity inspection, the sensitivity of thinner, paper chromatography high3. Mixture analysis, such as the main signal does not overlap, without separation can determine the proportion of the mixture.4. Proton exchange, the rotation of a single bond, the transformation of the ring and other chemical changes in the speed of the presumption1. the spin of the nucleusOf the isotopes of all elements, about half of the nuclei have spin motion. These spin nuclei are the object of nuclear magnetic resonance. Spin Quantum: The number of quantum numbers describing the spin motion of the nucleus, which can be an integer, a half integer, or a zero.In the organic compound composition elements, C, H, O, N is the most important element. In its isotopes, 12C, 16O are non-magnetic and therefore do not undergo nuclear magnetic resonance. 1H natural abundance of large, strong magnetic, easy to determine, so the NMR study was mainly for the proton. 13C abundance is small, only 12C 1.1%, and the signal sensitivity is only a proton to get 1/64. So the total sensitivity of only 1/6000 of 1H, more difficult to determine. But in the past 30 years, nuclear magnetic resonance instrument is greatly improved, can be measured in a short time 13C spectrum, and give more information, has become the main means of NMR. 1H, 19F, 31P natural abundance of large, strong magnetic, and nuclear charge distribution of spherical, the most easy to determine.2. Nuclear magnetic resonance phenomena① Precession: Spin with a certain magnetic moment Under the action of external magnetic field H0, this core will form angle for the kinematic motion: is the precession kinematic velocity, which is proportional to H0 (external magnetic field strength).② spin nuclear in the external magnetic field orientation: no external magnetic field, the spin magnetic orientation is chaotic. The magnetic core is in the external magnetic field H0, with (2I + 1) orientation. The spin of the magnetic core in the external magnetic field can be analogous to the precession (pronation, swing) of the gyroscope in the gravitational field.③ conditions of nuclear magnetic resonanceThe magnetic resonance magnetic field must have the magnetic nuclei, the external magnetic field and the RF magnetic field. The frequency of the RF magnetic field is equal to the precession frequency of the spin nucleus, and the resonance occurs from the low energy state to the high energy state.④ nuclear magnetic resonance phenomenon:In the vertical direction of the external magnetic field H0, a rotating magnetic field H1 is applied to the precession nucleus. If the rotational frequency of H1 is equal to the rotational precession frequency of the nucleus, the precession nucleus can absorb energy from H1 and transition from low energy state to high energy state Nuclear magnetic resonance.3. Saturation and relaxationLow energy nuclear is only 0.001% higher than high energy nuclear. Therefore, the low energy state core is always more than the high energy nuclear, because such a little surplus, so can observe the absorption of electromagnetic waves. If the nuclear continuous absorption of electromagnetic waves, the original low energy state is gradually reduced, the intensity of the absorption signal will be weakened, and ultimately completely disappeared, this phenomenon is called saturation. When saturation occurs, the number of cores in the two spin states is exactly the same. In the external magnetic field, the low-energy nuclei are generally more nuclear than the high-energy state, absorb the electromagnetic wave energy and migrate to the high-energy state of the core will be released by a variety of mechanisms of energy, and return to the original low energy state, this process called relaxation.4. Shield effect – chemical shift① ideal state of resonanceFor isolated, bare nuclei, ΔE = (h / 2π) γ · H;Under certain H0, a nucleus has only one ΔEΔE = E outside = hνOnly the only frequency ν of absorptionSuch as H0 = 2.3500T, 1H absorption frequency of 100 MHz, 13C absorption frequency of 25.2 MHz② real core: shielding phenomenonNuclear outside the electron (not isolated, not exposed)In the compounds: the interatomic binding (role) is different, such as chemical bonds, hydrogen bonds, electrostatic interactions, intermolecular forcesImagine: In H0 = 2.3500 T, due to the outer electrons of the shield, in the nuclear position, the real magnetic field is slightly smaller than 2.3500 TResonance frequency slightly higher than 100 MHzHow much is it? 1H is 0 to 10, and 13C is 0 to 250The hydrogen nuclei have electrons outside, and they repel the magnetic field lines of the magnetic field. For the nucleus, the surrounding electrons are shielded (Shielding) effect. The greater the density of the electron cloud around the core, the greater the shielding effect, the corresponding increase in magnetic field strength to make it resonant. The electron cloud density around the nucleus is affected by the connected groups, so the nuclei of different chemical environments, they suffer from different shielding effects, their nuclear magnetic resonance signals also appear in different places.③ If the instrument is measured with a 60MHz or 100MHz instrument, the electromagnetic wave frequency of the organic compound proton is about 1000Hz or 1700Hz. In determining the structure, the need to determine the correct resonant frequency, often requires several Hz accuracy, generally with the appropriate compound as the standard to determine the relative frequency. The difference between the resonant frequency of the standard compound and the resonant frequency of a proton is called the chemical shift.5. H NMR spectroscopy informationThe number of signals: how many different types of protons are present in the moleculeThe position of the signal: the electronic environment of each proton, the chemical shiftThe intensity of the signal: the number or number of each protonSplit situation: how many different protons are presentThe chemical shift of common types of organic compounds① induced effect② conjugate effectThe conjugation effect is weak or enhanced by proton shielding due to the displacement of the π electrons③ anisotropic effectIt is difficult to explain the chemical shift of H with respect to pi-electrons, and it is difficult to explain the electronegativity④ H key effectROH, RNH2 in 0.5-5, ArOH in 4-7, the range of change, the impact of many factors; hydrogen bonding with temperature, solvent, concentration changes significantly, you can understand the structure and changes related to hydrogen bonds.⑤ solvent effectBenzene forms a complex with DMF. The electron cloud of the benzene ring attracts the positive side of the DMF, rejecting the negative side. α methyl is in the shielding region, the resonance moves to the high field; and β methyl is in the masking region, the resonance absorption moves to the low field, and the result is that the two absorption peak positions are interchanged.
Ngu?n: Meeyou cacbua

First, the basic concept of particle size analysis(1) particles: with a certain size and shape of small objects, is the basic unit of the composition of the powder. It is very small, but microscopic but contains a lot of molecules and atoms;(2) particle size: the size of particles;(3) particle size distribution: a certain way to reflect a series of different particle size particles, respectively, the percentage of the total powder;(4) the representation of the particle size distribution: table method (interval distribution and cumulative distribution), graphical method, function method, common R-R distribution, normal distribution;(5) particle size: the diameter of particles, usually in microns as a unit;(6) Equivalent particle size: When a particle of a physical properties and homogeneous spherical particles the same or similar, we use the spherical particles straightDiameter to represent the diameter of the actual particles;(7) D10, the cumulative distribution of 10% of the corresponding particle size; D50, the cumulative distribution of the percentage reached 50% of the corresponding particle size; also known as the median or median particle size; D90, the cumulative distribution of the percentage reached 90% of the corresponding particle size; D (4,3) volume or mass average particle size;Second, the commonly used particle size measurement method(1) sieving method(2) sedimentation method (gravity sedimentation method, centrifugal sedimentation method)(3) resistance method (Kurt particle counter)(4) Microscope (image) method(5) Electron microscopy(6) ultrasonic method(7) breathable method(8) laser diffraction methodAdvantages and disadvantages of various methodsSieve method: Advantages: simple, intuitive, low cost of equipment, commonly used in samples larger than 40μm. Disadvantages: can not be used for 40μm fine sample; results by human factors and sieve deformation of a greater impact.Microscope: Advantages: simple, intuitive, can be morphological analysis. Disadvantages: slow, poor representative, can not measure ultra-fine particles.Sedimentation method (including gravity settlement and centrifugal settlement): Advantages: easy to operate, the instrument can run continuously, low price, accuracy and repeatability is better, the test range is larger. Disadvantages: test time is longer.Resistance method: Advantages: easy to operate, the total number of particles can be measured, the equivalent concept clear, fast, good accuracy. Disadvantages: the test range is small, easy to be blocked by particles, the media should have strict electrical characteristics.Electron microscopy: Advantages: suitable for testing ultrafine particles or even nano-particles, high resolution. Disadvantages: less sample, poor representation, the instrument is expensive.Ultrasonic method: Advantages: direct measurement of high concentrations of pulp. Disadvantages: low resolution.Ventilation method: Advantages: instrument prices are low, do not have to disperse the sample, magnetic particles can be measured powder. Disadvantages: can only get the average particle size, can not measure the particle size distribution.Laser method: Advantages: easy to operate, fast test, test range, repeatability and accuracy, and can be measured online and dry. Disadvantages: the results affected by the distribution model, the higher the cost of the instrument.Third, the basic principle of laser particle size analyzerLaser diffraction technology began in the small angle scattering, so this technology also has the following name:Fraunhofer diffraction method(Approximately) positive light scattering methodSmall angle laser scattering method (LALLS)At present, this range of technology has been expanded to include light scattering within a wider range of angles, in addition to the approximate theory such as Fraunhofer diffraction and irregular diffraction, and the Mie theory is now used by instrument manufacturers Theory as one of the important advantages of its products.Mickey’s theory is named after a German scientist. It describes the uniform spherical particles in the uniform, non-absorbing medium and its surroundings in the space of the radiation, the particles can be completely transparent or can be completely absorbed. The Millerian theory describes that light scattering is a resonance phenomenon. If a specific wavelength of the beam encounters a particle, the particle produces an electromagnetic vibration at the same frequency as the emitted light source – irrespective of the wavelength of the light, the particle diameter, and the refractive index of the particles and the medium. The particles are tuned and received at a specific wavelength, and the energy is re-emitted within a particular spatial angular distribution as well as a relay. According to the Mie theory, it is possible to produce multiple oscillations of various probabilities, and there is a certain relationship between the cross section of the optical action and the particle size, the wavelength of light and the refractive index of the particles and the medium. If you use the Mie theory, you must know the refractive index and absorption coefficient of the sample and the medium.Fraunhofer theory is named after a German physicist, Franco and Fader, which is based on scattering at the edge of the grain and can only be applied to completely opaque particles and small angles of scattering. When the particle size is less than or equal to the wavelength, the Fraunhofer assumption that the extinction coefficient is constant is no longer applicable (it is an approximation of the Mie theory, that is, ignoring the Mi’s theory of imaginary subsets and ignoring the light scattering coefficient and Absorption coefficient, that is, all the dispersant and dispersive optical parameters are set to 1, the mathematical treatment is much simpler, the color of the material and small particles are also much larger error. The approximate Mickey theory is not applicable to the emulsion ).The laser particle size analyzer is based on the phenomenon of light diffraction, when the light through the particles when the diffraction phenomenon (its essence is the interaction of electromagnetic waves and substances). The angle of the diffracted light is inversely proportional to the size of the particle.Different sizes of particles through the laser beam when the diffraction light will fall in different positions, the location information reflects the particle size; the same large particles through the laser beam when the diffraction light will fall in the same position. The information of the diffracted light intensity reflects the percentage of particles of the same size in the sample.The laser diffraction method uses a series of photodetectors to measure the intensity of the diffracted light at different angles of the particle size of the particle, using the diffraction model, through the mathematical inversion, and then the particle size distribution of the sample.And the diffracted light intensity received by the position detector gives a percentage content of the corresponding particle size.The dependence of the intensity of the diffracted light on the particles decreases with the decrease of the particle size. When the particles are as small as several hundred nanometers, the diffraction intensity is almost completely dependent on the angle, that is, the diffracted light at this time Distributed in a wide range of angles, and the light intensity per unit area is very weak, which increases the difficulty of detection.The measurement of samples under 1um and wide particle size ranges (tens of nanometers to several thousand micrometers) is the key to the laser diffraction granulator. In general, the following techniques and optical path configurations are used:1, multi-lens technologyThe multi-lens system was widely adopted before the 1980s, using a Fourier optical path configuration, where the sample cell was placed in front of the focusing lens and equipped with a number of different focal lengths of the lens to accommodate different particle size ranges. The advantage is simple design, only need to be distributed in the tens of degrees range of focal plane detector, the cost is low. The disadvantage is that if the sample size is wide when the need to replace the lens, the results of different lenses need to be split, for some unknown particle size of the sample with a lens measurement may lose the signal or due to process changes caused by changes in sample size can not be timely reflect.2, multi-light technologyMulti-light source technology is also used in the Fourier optical path configuration that the sample cell in front of the focusing lens, generally only distributed in the range of tens of degrees angle detector, in order to increase the relative detection angle, so that the detector can receive small particles Diffracting the optical signal, and disposing the first or second laser at different angles relative to the optical axis of the first light source. The advantage of this technique is that it is only a detector that is distributed over several tens of degrees, and the cost is low. The measurement range, especially the upper limit, can be wide. The disadvantage is that the small area detector distributed in the small angle range is also used for small Particle measurement, due to the small particles of diffracted light in the unit area of the signal is weak, resulting in small particles when the signal to noise ratio is reduced, which is why the multi-light source system in the measurement range of more than 1500 microns or so, to ensure that a few microns The following small particles of accurate measurement, the need to replace the short focal length of the focus lens. In addition, the multi-lens system in the measurement of samples, the different lasers are turned on, and in the dry measurement, because the particles can only pass through the sample pool, only one light source can be used for measurement, so the general use of multi-lens technology The lower limit of the dry size is less than 250 nm.3, multi-method hybrid systemMulti-method hybrid system refers to the laser diffraction method and other methods of mixing design of the particle size analyzer, laser diffraction part of the distribution only a few tens of degrees range of the detector, and then supplemented by other methods such as PCS, generally a few microns The above is measured by laser diffraction, and particles below a few microns are measured by other methods. Theoretically, the lower limit of the particle size depends on the lower limit of the auxiliary method. The advantage of this method is that the cost is low and the overall measurement range is wide, The best measurement conditions required by the method, such as the concentration of the sample are not the same, are often difficult to balance, and in addition to the systematic error between the different methods, it is often difficult to obtain the desired result in the data fitting area of the two methods unless It is known that the particle size of the sample only falls within the range of the diffraction method or within the range of the auxiliary method. In addition, the multi-method mixing system requires two different sample cells, which is not a problem for wet measurement because the sample can be recycled, but the sample can only be circulated through the sample cell for a dry process, Method of simultaneous measurement, so a variety of methods mixed system in the dry measurement of the lower limit of the particle size can only be hundreds of nanometers.4, non-uniform cross-wide compensation for wide-angle detection technology and anti-Fourier optical systemThe wide-angle detection of non-uniform cross-wide area compensation and the anti-Fourier optical system are developed in the late 1990s. The anti-Fourier optical path configuration is used to place the cell behind the focusing lens, In a very wide range of angles, the general physical detection angle of up to 150 degrees, so that a single lens to measure tens of nanometers to several thousand microns of the sample possible, optical schematic diagram shown in the design of the detector On the use of non-uniform cross and with the increase in the size of the detector area also increased the arrangement, both to ensure that the resolution of large particles when the measurement also ensures a small particle detection signal to noise ratio and sensitivity. No need to replace the lens and other methods can be measured from tens of nanometers to several thousand microns of particles, even the dry measurement, the lower limit can reach 0.1 microns. The disadvantage of this approach is that the cost of the instrument is high relative to the previous methods.The laser beam emitted from the laser is focused by a microscope, pinhole filter and collimator collimation, into a parallel beam of about 10 mm in diameter, the beam is irradiated onto the particles to be measured, a portion of the light is scattered, Leaf lens, the radiation to the radio and television detector array. Since the radio and television detector is on the focal plane of the Fourier lens, any point on the detector corresponds to a certain scattering angle. The array of radio and television detectors consists of a series of concentric rings, each of which is a separate detector capable of linearly converting the scattered light projected onto the above into a voltage and then sending it to a data acquisition card which converts the electrical signal Zoom in, after the A / D switch to the computer.Now the actual structure of the laser particle size instrument has played a great change, but the same principle.At present, people have come to the following conclusions: (1) measuring less than 1mm of particles, you must use the Mie theory;(2) measuring more than 1mm particles, if the lower limit of measurement of the instrument is less than 3mm, the instrument still use the Mie theory, or in the particle size distribution of 1mm near the “out of nothing” a peak;(3) The laser particle size analyzer can use the diffraction theory of the conditions: the lower limit of measurement of the instrument is greater than 3mm, or the measured particles are absorbent type, and the particle size is greater than 1mm;(4) As a universal laser particle size analyzer, as long as the lower limit of measurement is less than 1mm, whether it is used to measure large particles or small particles, should use the Mie theory.Fifth, the composition of laser particle size analyzerA light source (usually a laser) is used to produce a monochromatic, coherent and parallel beam; the beam processing unit is a beam amplifier with an integrating filter that produces a beam of expanded, near-ideal light beams to illuminate the dispersed particles (A coherent strong light source with a fixed wavelength, a He-Ne gas laser (λ = 0.63um).Particle disperser (wet and dry)Measure the scattering spectrum of the detector (a large number of photodiodes)Computer (for controlling equipment and calculating particle size distribution)Through technological advances, the lower limit of measurement can be 0.1um, some up to 0.02umSix, test operation steps1, preparation of equipment to install and disperse the liquid (gas)2, sample inspection, preparation, dispersion and sample concentration check the particle size range and particle shape and whether the full dispersion;3, measurement (select the appropriate optical model)4, the error from the diagnostic system of measurement error (deviation), can come from the incorrect sample preparation, deviation from the theoretical assumptions of the particles and / or due to improper operation and operation of the instrument caused;Seven, commonly used laser particle size meter manufacturersBritish Malvern laser particle size analyzer (abroad)Europe and the United States grams of laser particle size analyzer (Zhuhai)Dandong laser particle size analyzer (Liaoning)Eight, the test object1. All kinds of non-metallic powder: such as tungsten, light calcium, talc, kaolin, graphite, wollastonite, brucite, barite, mica powder, bentonite, diatomaceous earth, clay and so on.2. All kinds of metal powder: such as aluminum powder, zinc powder, molybdenum powder, tungsten powder, magnesium powder, copper powder and rare earth metal powder, alloy powder.3. Other powder: such as catalyst, cement, abrasive, medicine, pesticide, food, paint, dyes, phosphor, river sediment, ceramic raw materials, various emulsions.
Ngu?n: Meeyou cacbua

【introduction】The construction of flexible electronic devices with certain functions and structures provides a variety of possibilities for human life in the future, such as wearable electronic products, implantable chips, sensing skin, flexible robots, and so on. With the deepening of the research on luminescent materials, these creative products are moving from the laboratory to people’s lives. For example, a clothing containing a light-emitting element, a detector built by an optical signal, a chip capable of releasing a drug through an optical signal, a chip that participates in a signal transmission, and the like. Early research, mainly using screen printing technology, to achieve a large-scale manufacturing of AC flexible luminescent materials. Nowadays, with the advent of 3D printing technology, flexible materials with more complex structures are also produced.The researchers have designed a novel structure of light-emitting devices, which are mainly composed of four parts, namely, a pair of parallel stack or side by side distribution of the electrode, light-emitting layer, dielectric layer and a controllable electrode layer. The control of the electrode layer is achieved by selecting a different polarizing material or an electroconductive thin film. This new structure is not only simple, but also conducive to large-scale manufacturing, more importantly, compared with the traditional sense of the light-emitting devices, a pair of opposing electrodes are no longer stacked with each other, but side by side distribution. It is because of this structural advantage, the researchers have designed different types of devices. For example, this flexible material is mounted on an umbrella, and when the water falls on an umbrella, the umbrella glows, which also makes it possible to build a remote detector that utilizes optical signal changes.Figure 1. Comparison of conventional sandwich configurations of light emitting devices (denoted as S-ELS) and polarized electrode bridge light emitting devices (denoted PEB-ELS)a) Schematic diagram of the structure of a conventional sandwich device (S-ELS)b) Schematic diagram of polarization electrode bridge light emitting device (PEB-ELS)c) Flexible display of PEB-ELS;d) The backside of the PEB-ELS is enlarged with an electrode width of 0.45 mm and a pitch of 0.40 mm.e) the water shines on the PEB-ELS;f) Comparison of changes in AC voltage before and after water dumping.Figure 2. Effect of bridging material, voltage and frequency on PEB-ELS performancea) PEB-ELS positive partial magnification, electrode width of 1.5 mm, spacing of 0.4 mm;b) the addition of different bridging liquid, the light in the dark situation;c) the relationship between the luminous intensity and the type and concentration of the bridged liquid at a voltage frequency of 2 kHz;d) the effect of substrate impedance on the luminous intensity, insert the picture shows the relationship between liquid contact time and luminous intensity;e) the relationship between the luminous intensity and the voltage frequency when the voltage is constant;f) Draw a Picasso painting on PEB-ELS with a pencil.Figure 3. Polarized electrode bridge experiment.a-b) bridging the experimental diagram, the first PEB-ELS is divided into two parts, and then use the hydrogel as a polarized bridge, the two parts connected to test;c) half of the PEB-ELS infiltrated in the two beakers;d) Transparent polyacrylamide hydrogel for bridging, 5 cm long, 1.6 cm wide, 0.3 cm thick;e) After the two beakers are connected with a hydrogel, the voltage is applied and the PEB-ELS emits light;f) Place the hydrogel directly on PEB-ELS and the material glows.Figure 4. Preparation and performance testing of rainwater sensorsa-b) rainwater sensor preparation diagram;c-d) rainwater sensor of the physical map, white and dark;e) hand as bridge electrode, PEB-ELS light;f) When the water is frozen, the emission intensity of PEB-ELS is weakened.【summary】This study presents a new, low-cost, flexible, light-emitting device that can be mass-produced. In this paper, the luminescence performance of the device is studied, and the relationship between the luminescence performance and the bridging material and the applied voltage is discussed. And then made it based on the optical signal sensor. When the umbrella is wet or touched by hand, the contact surface will light. Not only that, this new type of light emitting device can also be used to write, when writing with a pencil, the corresponding area can also light. This also provides a new possibility for the future development of touch display technology.
Ngu?n: Meeyou cacbua