Stainless Steel
Twill Weave Mesh is a kind of wire cloth product with flat and smooth mesh,
uniform mesh, no deformation, good extensibility and abrasion resistance. Twill weave Stainless Steel Mesh warp and weft threads interwoven from the adjacent strands - weaving in the direction of silk and shuttle.The movement of this upper and lower knitting is the movement of the shuttle.Twill weaving can be used to weave different specifications of mesh and mesh screen.
Material: 201,
304, 304 (L), 310, 316 (L), etc
Features: Features: stainless steel twill weave net is an acid, alkali
resistant, high temperature, tensile and wear resistance strong product, has
the filtering precision, the load strength high characteristics.
USES: Twill weave stainless steel mesh is widely used in aerospace,
petroleum, chemical industry, scientific research and transportation, etc, used
in acid, alkali environment conditions screening and filter, oil industry as
mud mesh, chemical fiber industry as screen mesh, plating industry as pickling
nets.
Extra tip: Stainless steel twill wire mesh gauge packaging must be strict, outer
waterproof paper - moistureproof film - cushion film - cardboard packaging
products in order to prevent wooden - damp impact in the transport process.
The warp wire (D1) : all longitudinal
braided lines.
The weft wire (D2) : all horizontal weaving
lines.
Aperture (L1 and L2) : the distance between
two meridians or two weft.
Mesh number:number of metal mesh holes per inch.
Thickness (T) : thickness of the net.
Specifications:
SPEC
WIRE DIAMETER
APERTURE
OPENING
RATE
WEIGHT(POUND)
INCH
MM
INCH
MM
200X200
.0021
.0533
.0029
.0737
33.6
6.2
250X250
.0016
.0406
.0024
.0610
36.0
4.4
270X270
.0016
.0406
.0021
.0533
32.2
4.7
300X300
.0051
.0381
.0018
.0457
29.7
3.04
325X325
.0014
.0356
.0017
.0432
30.0
4.40
400X400
.0010
.0254
.0015
.370
36.0
3.3
500X500
.0010
.0254
.0010
.0254
25.0
3.8
635X635
.0008
.0203
.0008
.0203
25.0
2.63
Products Photoes:
Stainless Steel Twill Weave Mesh Stainless Steel Twill Weave Mesh,Stainless Steel Wire Cloth,Twill Weave Mesh,Stainless Mesh Wire Anping Xinzheng Metal Wire Mesh Co., Ltd , http://www.sievingmesh.com
On the one hand, the electronic product market is booming; on the other hand, as the "world's largest manufacturing power", the level of electronic manufacturing has lagged behind the West for a long time. The main technologies of China's electronic manufacturing rely on imports, and the core technology is tightly sealed by foreign countries. This not only causes the country to spend huge amounts of foreign exchange reserves to purchase patent technology every year, but also greatly restricts the long-term development of China's electronics manufacturing industry.
Ultra-precision surface polishing, modification and testing technology is one of the key technologies in advanced electronics manufacturing. It is mainly used in the surface of computer hard disk heads in the field of magnetic recording and the polishing of the surface of hard disk substrates. It is also used in the field of integrated circuits. Processing of silicon wafer processing and light-emitting diode (LED) sapphire substrates in the semiconductor field. Therefore, the breakthrough of this technology will have a greater impetus to China's electronic manufacturing industry on the road of independent innovation.
Prof. Jianbin Jian, Prof. Lu Xinchun, Associate Professor Pan Guoshun, and Academician Wen Shizhu of the State Key Laboratory of Tribology in our school have carried out many years of research in this field and made great progress.
Starting from the "needle tip"
As we all know, the computer hard disk we usually use has a limit on the amount of storage, and the amount of storage is determined by its storage density. The greater the storage density, the greater the storage capacity of a single disk. The storage density has many influencing factors, and the read/write capability of the head/disk, the performance of the surface protective film and the surface smoothness are all very important factors. Among them, the read and write ability of the magnetic head is mainly affected by the flying height of the magnetic head, except that it is closely related to material properties and line width. A magnetic head is like a flashlight. The electromagnetic waves emitted by it are not parallel, but have a certain opening angle. The closer the head is to the disk, the smaller the area of ​​the electromagnetic wave emitted on the surface of the disk, which increases the storage density and increases the storage capacity of the hard disk. The head surface protection film protects the magnetic head mainly from two important aspects: first, it must have good self-cleaning property to avoid excessive adsorption of impurities on the magnetic head; second, it must protect the magnetic head when the magnetic head and the hard disk start to operate, avoiding static friction. The force is too large and the magnetic head is worn. Therefore, it must also have a good bonding force with the magnetic head to prevent it from coming off the surface of the magnetic head when the magnetic head is sheared at a high speed.
With the development of the times and the advancement of the electronics industry, the requirements for the storage density of hard disks are getting higher and higher, the flying height of the magnetic head is continuously reduced, the probability of collision of magnetic heads and disks is increasing, and the performance of the protective film must be correspondingly Upgrade. Yan Jianbin's research group combines tribology with electronics manufacturing. Since 2000, he has focused on this direction and concentrated on the surface modification, processing and measurement problems in hard disk manufacturing. They fought for a few years on a small magnetic head, moving forward one nanometer and one nanometer, often "there is no way to reconcile the mountains and waters, and the village is dark and clear."
In the field of computer hard disk manufacturing, every one nanometer of flying height is faced with a series of huge technical challenges. Taking the surface polishing of the magnetic head as an example, the read/write area of ​​the magnetic head is composed of ferromagnetic material, wire (gold), base (aluminum oxide) and other materials, which need to be uniformly removed. Secondly, the ferromagnetic material is highly corrosive, and it requires processing. The anion concentration of the liquid is below 10-9; further, the closer the head is to the surface of the disk, the easier it is to rub against it, which requires the disk surface to be smoother (roughness below 0.1 nm). In addition, as the flying height of the magnetic head is lowered, how to protect the surface of the magnetic head from abrasion is also a problem.
The research team led by Yan Jianbin has cooperated with computer heads and disk production companies to carry out many years of research and achieved a series of technological breakthroughs, which reduced the surface roughness of the magnetic head from the original 0.483nm to 0.114nm. The surface roughness has reached 0.1 nm or less; the moisture resistance and bonding strength of the surface protective film of the magnetic head are obviously enhanced, and it exhibits good anti-pollution ability and anti-wear ability in the 20,000 start-stop experiments, thereby improving the storage density of the hard disk. Played a facilitating role.
Heavenly rewards unexpected gains
During the research process, the research group creatively proposed to introduce nano-diamond particles into the polishing liquid of the magnetic head surface, and use the polishing liquid containing ultra-fine diamond particles to interact with the alumina surface of the magnetic head, so that the surface roughness of the magnetic head can be greatly reduced. To their delight, the use of nano-diamond polishing fluids also removes scratches and black spots from the surface of the magnetic head during polishing, contributing to the improved read and write capabilities of the magnetic head.
In addition, Professor Meng Yonggang of the research group made innovations in the measurement method of the flying height of the magnetic head, and established a flying height measuring instrument to increase the resolution to 0.1 nm, reaching the international advanced level.
After a major breakthrough in the head polishing fluid, the research team further expanded their research scope and achieved more fruitful results: such as silicon wafer polishing in the field of integrated circuits, polishing rate, surface roughness of silicon wafers, and polishing fluid cycle life. The key indicators are higher than the foreign advanced polishing liquids, which has reached the technical level of replacing foreign advanced products. In the semiconductor field of light-emitting diode (LED) sapphire substrate polishing, the polishing rate is low and the surface scratches are solved in the sapphire polishing process. And problems such as large surface roughness. Yan Jianbin said that he did not expect to have these gains.
Flexible and efficient organization mode
Often, college research teams tend to react to the market more slowly than companies. Especially in the ever-changing IT industry, the research speed of college teams is relatively slow. Therefore, there are some difficulties in the research of application techniques such as ultra-precision surface polishing, modification and testing techniques.
In order to solve this problem, the State Key Laboratory of Tribology of our school cooperated with Shenzhen Research Institute to establish a laboratory that works closely with the company as a “division†that directly faces the market, thus achieving school-based support. Closely connected with the market, from basic theoretical research to technical seamless research and application. In Tsinghua’s “headquartersâ€, it mainly conducts forward-looking, theoretical and tentative basic research to seek the possibility of technological breakthroughs; in Shenzhen “divisionâ€, it faces the rapidly changing market conditions and conducts rapid response application research. Pursue the stability of technical applications. In this way, the functions of the two places are separated, but they can support each other and cooperate effectively. When the team found the possibility of breaking through key technologies in Beijing, Shenzhen could concentrate its efforts, quickly achieve breakthroughs and put them into practice and application, effectively solving the problem that scientific research results could not be converted into actual products in time.
Multidisciplinary team composition
In addition to the above-mentioned fruitful cooperation model of division of labor, having a diverse and dynamic team of disciplines is also an important factor in their success on the scientific research road.
The ultra-precision surface polishing, modification and testing technology project team was originally initiated by Qi Jianbin, Lu Xinchun, Wen Shizhu, etc., plus some students participated. With the development of the project, a lot of "fresh blood" has been added. However, for the special research field of nanofabrication, the team urgently needs researchers with different knowledge backgrounds in materials, chemistry, physics and mechanics. At the beginning of the project, how to solve the problem of reasonable configuration of professionals in the team has become a problem that has plagued them for a long time. At this time, the relatively flexible advantages of the Shenzhen Research Institute system were revealed. The research team recruited researchers from a variety of disciplines through contractual methods, thus forming a comprehensive research team including professionals in mechanics, chemistry, materials, and machinery, which greatly eased the bottleneck of professional configuration. In recent years, they have gradually adopted this approach in Tsinghua’s “headquartersâ€, which further optimized the composition of the team’s internal staff and effectively promoted the project.
Yan Jianbin said with gratitude that after years of exploration, integration and development, their National Key Laboratory of Tribology ranked first in the evaluation of 34 key laboratories in the national engineering category.
Focus on breaking into the international big cycle
Ultra-precision surface manufacturing is a cutting-edge technology, and international competition is fierce. Yan Jianbin said frankly: "To achieve this level, although it is temporarily synchronized with the international advanced level, if it is slightly lax, it is likely to fall behind in two years. This research is difficult, fast, and tired. At present, in the field of single crystal silicon polishing liquid, the research results of our school have been synchronized with the world's leading DuPont company. The polishing fluid developed by the research team can be recycled for more than 60 hours, even superior to DuPont's 50-hour level. Several domestic companies have adopted the results of our school through comparative experiments. "In this field, people use only the best of the world's top two products, and they don't choose the third one. We don't want to replace anyone, but we must enter this international cycle."
When asked how to achieve today's results, Yan Jianbin particularly emphasized a word --- focus. In his own case, since 1991, he has been doing lubrication and polishing research for nearly 20 years, and has been closely surrounding this direction, combining theory, technology and application. It is no accident that we can achieve today’s results.
Referring to the plan for the future, Zhai Jianbin said that the research team will continue to focus on breakthroughs, do a good job in each specific link, and firmly occupy a place in the international cycle. "If we go to this stage, we need to use our Tsinghua--whether it is theory, technology or products, then we will succeed."
Touching the stone across the river, getting wider and wider
Although great progress has been made in the polishing and modification of magnetic heads, magnetic disks and monocrystalline silicon wafers, Zhai Jianbin admits that at the beginning, they themselves are not sure how much prospects this project can have, just Hold the attitude of trying and cross the river by feeling the stones. At the same time, the lack of funds in the initial stage of the project and the structural defects caused by the limited background of the researchers also brought certain difficulties to the research work. In addition, team member Pan Guoshun needs most of the time to work hard in Shenzhen, away from school and family, and there are many inconveniences in life. In the face of multiple pressures, with the support of the academician Wen Shizhu, the team did not waver. After seeing this road, it has been firm and steady. In this way, Qi Jianbin and his team started to cross the river, and finally embarked on a “Bangzhuang Avenueâ€: all kinds of technical difficulties were overcome, and the research project was understood and recognized by the insiders; “973 Planâ€, The support of the National Natural Science Foundation and major national special projects has also provided sufficient guarantee for research funding; the team size has gradually expanded and the team structure has become increasingly perfect. On the basis of the third prize of the National Technology Invention and the Second Prize of the National Natural Science Science, which was won by Wen Shizhu, the team won the second prize of National Science and Technology Progress Award in 2008.
In the process, every member of the team has worked hard and made many sacrifices. Sometimes, in order to produce a sample within a limited time, they have to work overtime for a long time; sometimes for research purposes, some teachers must stay in the laboratory in Shenzhen for many years, and it is rare to return home several times a year... Yan Jianbin said with deep feelings: "The achievement of achievements is the result of the joint efforts of team members over the years, and everything is in order."
The new application of nano-diamond - "Super-precision surface polishing, modification and testing technology and its application" led by Prof. Jianbin Jian won the second prize of National Science and Technology Progress Award
Advanced electronics manufacturing is at the forefront of manufacturing technology, and its level represents the level of manufacturing in a country. However, China is faced with such a dilemma: