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Nitrogen-vacancy (NV) centers in diamond are of great interest and promise in solid-state quantum emitters, however, the possibility of coupling NV centers with photonic or broadband plasmonic nanostructures for ultrasensitive biolabeling has not yet been fully realized . Indeed, fabrication of free-standing hybrid diamond imaging nanoprobes with enhanced brightness and high temporal resolution properties remains challenging. Therefore, there is an urgent need to develop an efficient and general strategy for efficient coupling of nanodiamond NV centers to plasmons. Recently, Nano Letters ("Nano Letters") published online the research progress of the Liang Le research group of the Institute for Advanced Study of Wuhan University and the Ishan Barman research group of Johns Hopkins University on the research progress of nanodevices for efficiently constructing plasma-enhanced NV color centers. They used the following The upward DNA self-assembly method has developed a hybrid free-standing plasmonic nanodiamond. By constructing a closed plasmonic nanocavity, the complete subassembly of a single nanodiamond can be achieved with extremely high efficiency, thereby significantly accelerating the formation of the NV center of the nanodiamond. Transition rates, associated single-nanoparticle spectroscopic characterizations reveal significantly enhanced brightness and emission rates of plasmonic nanodiamonds. Taking advantage of the versatility of DNA self-assembly, we achieved the creation of nanoassemblies with multiple variants of nanodiamond and gold nanoparticle combinations of different sizes. Through a systematic study of the structure and properties, a causal relationship between the transition dynamics and the plasmonic nanocavity was found, and the closed plasmonic nanocavity was demonstrated to be superior to the open or semi-open nanocavity.

Nanodiamonds in Space: Applications in Satellites Nanodiamond is a unique material with properties that make it ideal for a range of applications, including the aerospace and satellite industries. This article provides an overview of nanodiamonds, their applications, commercial examples and prospects in the aerospace and satellite industries. Nanodiamond: A Unique Material Nanodiamond is a promising material with wide applications in various fields such as aerospace and satellites. It is produced by the nanotube hitting the target at high speed. This process causes the nanotubes to break down, forming tiny diamond particles smaller than 10 nanometers. Due to its unique properties, nanodiamonds have attracted extensive attention in recent years. They are known for their excellent mechanical, optical and thermal properties, making them ideal for a variety of applications. One of the most interesting properties of nanodiamonds is their hardness. They are one of the hardest materials known, approaching the hardness of natural diamonds. As a result, nanodiamonds are highly wear-resistant, making them ideal for applications where durability is critical. Nanodiamond also has excellent thermal conductivity, making it useful in applications where heat dissipation is important. They also have unique optical properties with broad absorption spectra, ranging from the ultraviolet to the near-infrared region of the electromagnetic spectrum, making them useful in a range of optical applications, including use as fluorescent markers and as components in optical devices. Applications and advantages of nanodiamonds in aerospace and satellites Nanodiamonds have many applications in the aerospace and satellite industry, and one of the main uses is as a coating material. The coating is applied to components and surfaces of aircraft, satellites and rockets to provide enhanced mechanical and thermal performance. The use of nanodiamond coatings can improve the wear resistance, corrosion resistance and thermal conductivity of components. Additionally, nanodiamond coatings could improve the efficiency of propulsion systems by reducing friction and wear. Another application of nanodiamonds is the development of composite materials. Composites are widely used in the aerospace industry due to their light weight and high strength properties. Nanodiamonds can be added to the matrix material of composites to increase their strength and durability, as well as improve their thermal and electrical properties. Nanodiamonds are also used in lubrication and polishing applications. Due to their hardness and low coefficient of friction, they can be used as additives in lubricants to improve their performance. Likewise, they can be used in polishing applications to produce high-quality, scratch-free surfaces. Practical Applications of Nanodiamonds in Aerospace and Satellites Several companies and research groups are working on nanodiamonds for aerospace and satellite applications. Finnish nanodiamond manufacturer Carbodeon is one such company. Carbodeon produces nanodiamond coatings for the aerospace and satellite industries. Their coatings are applied to turbine blades and rocket nozzles to improve their performance. Carbodeon's nanodiamond coatings have been shown to increase component durability and wear resistance, as well as enhance thermal conductivity. Another company working on nanodiamonds is Element Six, a UK-based synthetic diamond manufacturer. Element Six produces nanodiamonds for composite and coating materials. Their nanodiamonds are used in the aerospace industry to improve the mechanical and thermal properties of components. For example, Element Six's nanodiamond composites have been shown to improve the fatigue resistance and damage tolerance of aircraft structures. A recent study published in the American Chemical Society journal ACS Applied Materials and Interfaces focused on the production of nanodiamonds for satellite applications by ballistic fragmentation of carbon nanotubes at different speeds. It turns out that such high-energy collisions cause atomic bonds in the nanotubes to break and, in some cases, reform into different structures.

Application of CVD diamond in diamond roller of worm gear grinding machine Worm gear grinding machine is a continuous generating grinding machine for spur and helical cylindrical gears, which is suitable for batch and professional gear processing and production. The basic process is to use diamond rollers to dress the worm wheel, and then use the worm wheel to grind the gear. The grinding process has high requirements on the precision and service life of diamond rollers. The principle of grinding gears of worm grinding wheel gear grinding machine is equivalent to the meshing principle of a pair of helical gears. The worm grinding wheel can be regarded as a helical gear with few teeth (the number of teeth of a single-head grinding wheel is equal to 1). Because of its small number of teeth, large helix angle and long teeth, it can make many turns around the axis, so it forms an involute worm whose normal base is equal to the normal base of the gear being ground. The meshing between the worm grinding wheel and the gear is regarded as the meshing between the processing gear and the imaginary rack formed by the worm grinding wheel along the normal section

Types, properties and characteristics of diamond tool materials and tool applications Diamond is an allotrope of carbon, and it is the hardest material found in nature. Diamond tools have high hardness, high wear resistance and high thermal conductivity, and are widely used in the processing of non-ferrous metals and non-metallic materials. Especially in the high-speed cutting of aluminum and silicon-aluminum alloys, diamond tools are the main types of cutting tools that are difficult to replace. Diamond tools that can achieve high efficiency, high stability, and long-life machining are indispensable and important tools in modern CNC machining. ⑴ Types of diamond tools ① Natural diamond tool: Natural diamond has been used as a cutting tool for hundreds of years. The natural single crystal diamond tool has been finely ground, and the cutting edge can be ground extremely sharp. The cutting edge radius can reach 0.002μm, which can realize ultra-thin cutting and can It is a recognized, ideal and irreplaceable ultra-precision machining tool for processing extremely high workpiece precision and extremely low surface roughness. ② PCD diamond tool: Natural diamond is expensive, and polycrystalline diamond (PCD) is widely used in cutting. Since the early 1970s, polycrystalline diamond (Polycrystauine diamond, PCD for short) was developed After success, natural diamond tools have been replaced by artificial polycrystalline diamond in many occasions. PCD raw materials are rich in sources, and its price is only a few tenths to one tenth of natural diamonds. PCD tools cannot grind extremely sharp edges, and the surface quality of the processed workpieces is not as good as that of natural diamond. It is not convenient to manufacture PCD inserts with chip breakers in the industry. Therefore, PCD can only be used for fine cutting of non-ferrous metals and non-metals, and it is difficult to achieve ultra-precision mirror cutting. ③ CVD diamond tools: From the late 1970s to the early 1980s, CVD diamond technology appeared in Japan. CVD diamond refers to the synthesis of diamond film on heterogeneous substrates (such as cemented carbide, ceramics, etc.) by chemical vapor deposition (CVD). CVD diamond has exactly the same structure and characteristics as natural diamond. The performance of CVD diamond is very close to that of natural diamond, and it has the advantages of natural single crystal diamond and polycrystalline diamond (PCD), and overcomes their shortcomings to a certain extent. ⑵ Performance characteristics of diamond tools ① Extremely high hardness and wear resistance: Natural diamond is the hardest substance found in nature. Diamond has extremely high wear resistance. When processing high-hardness materials, the life of diamond tools is 10 to 100 times that of cemented carbide tools, or even hundreds of times. ② It has a very low coefficient of friction: the coefficient of friction between diamond and some non-ferrous metals is lower than that of other cutting tools, the coefficient of friction is low, the deformation during processing is small, and the cutting force can be reduced. ③ The cutting edge is very sharp: the cutting edge of diamond tools can be sharpened, and the natural single crystal diamond tool can be as high as 0.002-0.008μm, which can be used for ultra-thin cutting and ultra-precision machining. ④ Has high thermal conductivity: diamond has high thermal conductivity and thermal diffusivity, cutting heat is easily dissipated, and the temperature of the cutting part of the tool is low. ⑤ Low thermal expansion coefficient: The thermal expansion coefficient of diamond is several times smaller than that of cemented carbide, and the change in tool size caused by cutting heat is very small, which is especially important for precision and ultra-precision machining that requires high dimensional accuracy. ⑶ Application of diamond tools Diamond tools are mostly used for fine cutting and boring of non-ferrous metals and non-metallic materials at high speed. It is suitable for processing various wear-resistant non-metals, such as FRP powder metallurgy blanks, ceramic materials, etc.; various wear-resistant non-ferrous metals, such as various silicon-aluminum alloys; various non-ferrous metal finishing processing. The disadvantage of diamond tools is that they have poor thermal stability. When the cutting temperature exceeds 700°C to 800°C, it will completely lose its hardness; in addition, it is not suitable for cutting ferrous metals, because diamond (carbon) is easy to bond with iron at high temperatures. The atomic action converts the carbon atoms into a graphite structure, and the tool is easily damaged.

In the modern world, no one can say that they have nothing to do with "semiconductors". The mobile phones we use every day, the computers we use, the TVs we watch, and the speakers we listen to all contain semiconductor components. It can be said that without semiconductors, there would be no semiconductors in the modern world. Lightweight and easy to use high-tech products. Diamond semiconductor is the technology and product of using artificial diamond as a semiconductor material. As a semiconductor material, diamond has excellent characteristics superior to other semiconductor materials. Here we briefly introduce the characteristics of diamond as a semiconductor. Diamond is far superior to other semiconductor materials in many aspects such as band gap, electron mobility, and thermal conductivity. . Compared with silicon carbide and gallium nitride, which have been commercially available, diamond has unparalleled characteristics, so it is known as the "ultimate semiconductor material". Based on the industry's long-term research and development activities, diamond semiconductors have now begun to gradually move towards practical application. However, it will still take a long time to popularize and promote the application of diamond semiconductors. However, it has been reported that within a few years at the earliest, there will be trial samples of diamond semiconductors. The more attention the industry pays to diamond semiconductors, the easier it is to gather advantageous resources and accelerate the speed of research and development. As an emerging semiconductor material, diamond semiconductor has attracted much attention. Recently, scientific research institutions and enterprises at home and abroad have continuously promoted the research and development of diamond semiconductors, and made some new progress. In the research and development of diamond semiconductors, Japanese R&D institutions have always been leading and have created many achievements. Even today, the research and development level of the Industrial Research Institute is second to none. However, research and development activities so far have been limited to laboratory verification work, and have not developed actual semiconductors that can be used in electronic circuits and equipment. Researchers recently published a paper introducing a new type of diamond semiconductor device. This device uses a sandwich structure, where two layers of boron nitride and one layer of graphene are grown on a diamond substrate, forming a "graphene/boron nitride/graphene/diamond" structure. According to the researchers, this device has high electron mobility and high thermal stability, which is expected to be used in high-power electronic devices, high-frequency communication and microwave radar and other fields. It is reported that Element Six, a start-up company in the field of diamond semiconductors, is planning to open a new production line in 2023 to meet the growth in market demand. Element Six has established several factories in Europe, Asia and North America, and has conducted research and development in the field of diamond semiconductors for many years. In addition, diamond semiconductors have shown broad application prospects in other fields. For example, in the field of power electronics, diamond semiconductors have the characteristics of low loss, high temperature stability, and high voltage tolerance, and are expected to be applied to high-power electronic devices; in the field of life sciences, diamond semiconductors can be used as biosensors to detect DNA and proteins and other molecules. In general, the continuous innovation and development of diamond semiconductors in new materials, new devices, and new technologies has brought broader application prospects to various industries. With the continuous advancement of technology and the continuous growth of market demand, the future of diamond semiconductor field is full of opportunities. Today, more and more universities and R&D institutions are promoting the research and development of diamond, and are pushing diamond semiconductors from the research and development stage to practical application. The key to whether the practical application and potential of diamond semiconductor can be promoted is whether it can cooperate with large enterprises. Regrettably, although the engineers of the company showed great interest at the press conferences of various R&D results, none of this has any direct connection with the business. It will take at least ten years to actually realize commercialization. time, and the results of R&D cannot directly and quickly bring profits, so companies have been hesitant. Therefore, real social applications cannot be realized only by universities and R&D institutions. In addition, not only semiconductors, diamonds can also be applied to quantum sensors. Diamond materials are important for future technologies such as the quantum internet. Special defect centers can act as qubits and emit individual particles of light called single photons. Scientists at Humboldt University of Berlin have integrated individual qubits into optimized diamond nanostructures. These structures, which are one time thinner than a human hair, can transfer emitted photons into the glass fibers in a directed manner. A characteristic of the diamond material used is the relatively high density of nitrogen impurity atoms in the crystal lattice. These may protect the quantum light source from electronic noise on the nanostructured surface. Coincidentally, we have also seen news recently that Amazon is working with the global diamond giant De Beers Group`s Element Six department to develop the project. Quantum networks use subatomic matter to transmit data in a way that surpasses today`s fiber optic systems. Diamond will be part of a component that allows data to travel farther without interruption. The application of this technology has also found new applications for industrial diamonds. It is believed that in the near future, the characteristics of diamond as a functional material will be applied to a wider range of fields and become a necessity in our daily life.

1. Definition and classification of diamond Diamond is composed of carbon and is the hardest substance in nature. It is an allotrope of amorphous carbon, graphite, carbon fiber, fullerene, carbon nanotube, graphene and other materials. According to different formation conditions, diamond can be divided into natural diamond and artificial diamond. The appearance, physical properties and chemical properties of the two are exactly the same, the difference is that the diamonds produced in the laboratory are usually small in size (currently the large particle manufacturing technology has been broken through), and the cost is low, the price is one-tenth of the natural diamond. The high cost of natural diamond mining, small reserves, and its non-renewable nature cannot be widely used in industrial production. Diamond is often classified according to its nitrogen content and spectral characteristics, and is divided into two types: type I and type II, which are further subdivided into types Ia, Ib and IIa, IIb. Since the color of diamond is controlled by impurity elements and lattice defects inside the crystal, the type of diamond is often closely related to its color. For example, natural type Ia diamond is usually colorless, brown, pink or violet; natural type Ib diamond is usually Brown, yellow or orange; natural type IIb diamonds are usually sky blue. 2. The development history of my country's diamond industry China's diamond industry started relatively late, and the industry has developed rapidly. At present, China's diamond manufacturing equipment has a competitive advantage in terms of technological content, diamond output and price in the world. The development of China's diamond industry has mainly experienced the exploration and development stage, the stable development stage, the rapid development stage and the high-speed development stage. Exploration and development stage (1963-1968) In 1963, the first artificial diamond manufactured by domestic double-sided top ultra-high pressure equipment was successfully developed, using high-purity graphite powder as raw material and nickel-chromium alloy as the catalyst, marking the beginning of the exploration and development of China's artificial diamond industry; In 1966, China's synthetic diamond output exceeded 10,000 carats, which was an important step in the development of the synthetic diamond industry. Stable development stage (1969-1991) In 1969, the No. 6 Grinding Wheel Plant, the first specialized production plant of artificial diamond and its products in China, was completed and put into operation, laying the foundation for the stable development of the industry; In 1971, China's synthetic diamond output exceeded 1 million carats for the first time, and the synthetic diamond industry entered a stage of stable development; In 1984, China's synthetic diamond production exceeded 10 million carats, and the industry's development gradually accelerated. Rapid development stage (1992-2010) In 1992, China's synthetic diamond production exceeded 100 million carats, and the industry entered the fast lane; In 2000, China's synthetic diamond output reached 1.2 billion carats, which were exported to 30 countries, and its competitiveness in the international market gradually increased; From 2000 to 2010, China's synthetic diamond industry was in a period of rapid growth, and the scale of production expanded rapidly, and the number of export countries and regions reached more than 60. High-speed development stage (2011-present) In 2011, the output of synthetic diamond exceeded 10 billion carats, the proportion of output in the international market continued to increase, and the industry continued to develop at a high speed; At the end of 2017, China's synthetic diamond production accounted for more than 90% of the world's total output, and China occupies an important position in the international synthetic diamond market; In 2018, China's synthetic diamond production was stable at between 14 billion carats and 16 billion carats. The scale of downstream applications continued to expand, and the industry was still in a stage of rapid development.

Diamond has excellent electrical properties: ultra-wide band gap, ultra-high breakdown field strength, high electron and hole mobility, and is expected to become the "ultimate semiconductor"; acoustically, diamond has the highest surface acoustic wave among all materials Speed and extremely high Young's modulus; optically, diamond can transmit photons that are smaller than the band gap energy from far infrared to ultraviolet; thermally, its thermal conductivity exceeds that of copper, so diamond has the potential for cross-field applications. Table 1 shows the properties of diamond materials and their corresponding application fields. Compared with the traditional diamond high temperature and high pressure (HPHT) synthesis method, the functional diamond mainly adopts (atmospheric pressure) chemical vapor deposition (CVD) method. CVD diamond is divided into CVD film (conventional diamond film, nano-diamond film, thickness less than 50 μm) and self-supporting thick film (single crystal diamond and polycrystalline diamond). According to the synthesis technology, it is divided into microwave-assisted type (MPCVD), hot wire type and DC type. MPCVD technology is currently the mainstream method for synthesizing high-quality diamond.

Drying of diamond powder After the diamond powder is prepared and undergoes steps such as impurity removal and sorting, the interior still contains moisture. Excessive moisture will easily cause the diamond powder to condense and affect its use. Choosing a scientific, fast and economical drying method is an important guarantee for the final high-quality micro-powder. After the finely purified diamond micropowder is rinsed, it can enter the final drying process of micropowder production. 1. The most likely problems in the drying process 1. Cross-contamination of products of different specifications; 2. Secondary pollution caused by drying equipment, utensils and environment; 3. Hardening, hard agglomeration and reduced dispersion of fine-grained products caused by high-temperature drying. 2. Equipment suitable for drying diamond powder 1. Direct heating drying equipment includes industrial electric furnace or electric heating plate, industrial induction cooker; 2. Indirect heating drying equipment includes temperature-controllable electric oven, steam drying oven, industrial microwave oven, etc.;

Recently, the Danish Institute for Advanced Study cooperated with Beijing University of Technology, Japan National Institute of Materials Science and Technology, University of Leuven in Belgium, Central South University, University of Bristol in the United Kingdom, University of Ghent in Belgium, etc., using chemical vapor deposition and micro-nano processing technology to prepare Nanoscale "diamond rings" were discovered, and metal-Bose semiconductor phase transitions and unconventional "giant magnetoresistance" effects were discovered in these "diamond rings". These findings provide new ideas for the design of superconducting quantum devices. The results of the research paper entitled Unconventional Giant [Magnetoresistance" in Bosonic Semiconductor Diamond Nanorings have been published in the scientific journal Advanced Materials. Materials can be roughly divided into insulators, semiconductors, conductors and superconductors according to their electrical properties. As the temperature decreases, the resistance of insulators and semiconductors tends to increase due to their non-zero bandgap. Metals are good conductors, and their electrical resistance usually decreases with decreasing temperature. Superconductors generally exhibit metal-like electrical properties at higher temperatures. At low temperatures, when the free electrons in a superconductor combine into Cooper pairs and quantum condense, their electrical resistance plummets to zero. At present, in addition to the familiar superconducting maglev trains, superconductors are also used to develop advanced quantum devices, such as single-photon detectors and quantum computers. A question that has plagued the physics and materials science community for a long time is: Does the formation of Cooper pairs necessarily lead to a phase transition from a metallic state to a superconducting state? This question was answered in collaboration with the above-mentioned international research team. The team selected boron-doped artificial diamond (diamond) as the raw material, and used advanced micro-nano processing technology to prepare a nanoscale diamond ring structure ("diamond ring"). These nano "diamond rings" exhibit metal-like electrical properties at relatively high temperatures, and their electrical resistance spikes rather than drops when cooled to the superconducting phase transition temperature of their raw materials. The occurrence of the anomalous phase transition is caused by the confinement of the Cooper pair by the nano "diamond ring". The formation of Cooper pairs is at the cost of the consumption of free single electrons. When the nano-"diamond ring" effectively acts as a quantum well for the Cooper pairs, the system will have "no electrical conduction", so the resistance soars. Because this phase transition is closely related to the formation and dynamics of Cooper pairs (bosons), the team defines it as a metal-Bose semiconductor phase transition. This discovery is fundamentally different from the traditional metal-insulator phase transition, which is often caused by the localization of single electrons (fermions). Accompanied by the occurrence of the metal-Bose semiconductor phase transition, the nano-"diamond ring" exhibits an unconventional "giant magnetoresistance" effect. The conventional giant magnetoresistance effect is caused by spin-related electron scattering, and is now widely used in computer hard disk data reading. The multilayer film structure composed of magnetic and non-magnetic materials is a key component of the hard disk read head. When the structure is placed in the magnetic field generated by the magnetic domain of the hard disk, the spin-related electron scattering will be suppressed, resulting in a significant reduction in the structure resistance. , so as to realize the identification and reading of data. Different from the conventional giant magnetoresistance effect, the "giant magnetoresistance" effect in the nanometer "diamond ring" is caused by the annihilation of Cooper pairs. In an external magnetic field, the Cooper pairs in the nanometer "diamond ring" are split into single electrons, and the release of these single electrons makes the system "electrically conductive", resulting in a sudden drop in resistance. This research reveals a series of novel quantum phenomena, expands the understanding of the traditional classification of materials, and provides a new physical basis, material platform and design ideas for the development of superconducting quantum devices. Professor Zhang Gufei from the Danish Institute for Advanced Study initiated the research and led the main research work with Professor Ke Xiaoxing from Beijing University of Technology, Chairman Liao Meiyong from the National Institute of Materials Science and Technology of Japan, Dr. Liu Liwang from the University of Leuven in Belgium, and Professor Li Yejun from Central South University. .

Market size and future development trend of China's superhard tool industry China's superhard tool industry is a rapidly developing industry with broad prospects. In 2014, the total output value of China's superhard tool industry reached 1.38 billion yuan, a year-on-year increase of 17.2%, an increase of 9.3% over 2013, and is expected to continue to grow in the next few years. According to the analysis of the 2023-2029 China superhard tool industry market competition model and investment prospect research report released by Market Research Online, with the development of Made in China 2025, China's superhard tool industry will usher in greater development opportunities. With the country's increasing investment in high-end manufacturing, the development trend of the superhard tool industry will strongly promote the growth of the superhard tool industry. In addition, as the government invests in the market, superhard cutting tool companies will also usher in more investment opportunities. At the same time, the needs of social and economic development will also promote the development of the superhard cutting tool industry. For example, in industries such as automotive manufacturing, the use of superhard cutting tools is increasing. In addition, superhard cutting tools are also used in aerospace,machinery manufacturing,electronic manufacturing and other industries, and the development of these industries will also promote the development of the superhard cutting tool industry. With the deepening of market development, the future development of China's superhard tool industry will be even more impressive. Due to the continuous improvement of superhard cutting tools, the product performance, production process and technical level of the superhard cutting tool industry have been improved, thereby enhancing the competitiveness of the superhard cutting tool industry. In addition, the superhard cutting tool industry will continue to use information technology and new energy technology to improve product quality and efficiency to meet market demand. It is estimated that by 2025, the market size of China's superhard tool industry will reach more than 3 billion yuan, and will continue to maintain a growth trend. In the future development, China's superhard cutting tool industry will continue to promote the innovation and development of the superhard cutting tool industry in combination with the development requirements of the national manufacturing 2025, improve the technical level of the industry, enhance the competitiveness of the industry, and meet the needs of the market.

Market size and future development trend of China's superhard tool industry China's superhard tool industry is a rapidly developing industry with broad prospects. In 2014, the total output value of China's superhard tool industry reached 1.38 billion yuan, a year-on-year increase of 17.2%, an increase of 9.3% over 2013, and is expected to continue to grow in the next few years. According to the analysis of the 2023-2029 China superhard tool industry market competition model and investment prospect research report released by Market Research Online, with the development of Made in China 2025, China's superhard tool industry will usher in greater development opportunities. With the country's increasing investment in high-end manufacturing, the development trend of the superhard tool industry will strongly promote the growth of the superhard tool industry. In addition, as the government invests in the market, superhard cutting tool companies will also usher in more investment opportunities. At the same time, the needs of social and economic development will also promote the development of the superhard cutting tool industry. For example, in industries such as automotive manufacturing, the use of superhard cutting tools is increasing. In addition, superhard cutting tools are also used in aerospace,machinery manufacturing,electronic manufacturing and other industries, and the development of these industries will also promote the development of the superhard cutting tool industry. With the deepening of market development, the future development of China's superhard tool industry will be even more impressive. Due to the continuous improvement of superhard cutting tools, the product performance, production process and technical level of the superhard cutting tool industry have been improved, thereby enhancing the competitiveness of the superhard cutting tool industry. In addition, the superhard cutting tool industry will continue to use information technology and new energy technology to improve product quality and efficiency to meet market demand. It is estimated that by 2025, the market size of China's superhard tool industry will reach more than 3 billion yuan, and will continue to maintain a growth trend. In the future development, China's superhard cutting tool industry will continue to promote the innovation and development of the superhard cutting tool industry in combination with the development requirements of the national manufacturing 2025, improve the technical level of the industry, enhance the competitiveness of the industry, and meet the needs of the market.

Market size and future development trend of China's superhard tool industry China's superhard tool industry is a rapidly developing industry with broad prospects. In 2014, the total output value of China's superhard tool industry reached 1.38 billion yuan, a year-on-year increase of 17.2%, an increase of 9.3% over 2013, and is expected to continue to grow in the next few years. According to the analysis of the 2023-2029 China superhard tool industry market competition model and investment prospect research report released by Market Research Online, with the development of Made in China 2025, China's superhard tool industry will usher in greater development opportunities. With the country's increasing investment in high-end manufacturing, the development trend of the superhard tool industry will strongly promote the growth of the superhard tool industry. In addition, as the government invests in the market, superhard cutting tool companies will also usher in more investment opportunities. At the same time, the needs of social and economic development will also promote the development of the superhard cutting tool industry. For example, in industries such as automotive manufacturing, the use of superhard cutting tools is increasing. In addition, superhard cutting tools are also used in aerospace,machinery manufacturing,electronic manufacturing and other industries, and the development of these industries will also promote the development of the superhard cutting tool industry. With the deepening of market development, the future development of China's superhard tool industry will be even more impressive. Due to the continuous improvement of superhard cutting tools, the product performance, production process and technical level of the superhard cutting tool industry have been improved, thereby enhancing the competitiveness of the superhard cutting tool industry. In addition, the superhard cutting tool industry will continue to use information technology and new energy technology to improve product quality and efficiency to meet market demand. It is estimated that by 2025, the market size of China's superhard tool industry will reach more than 3 billion yuan, and will continue to maintain a growth trend. In the future development, China's superhard cutting tool industry will continue to promote the innovation and development of the superhard cutting tool industry in combination with the development requirements of the national manufacturing 2025, improve the technical level of the industry, enhance the competitiveness of the industry, and meet the needs of the market.

A definition and classification of diamond powder Generally speaking, the powdery material for grinding and polishing with abrasive particle size less than 54 microns is called micropowder. The fine powder processed by using diamond as raw material is called diamond fine powder. In recent years, with the continuous expansion of new application fields, the particle size of many diamond micropowders has been much larger than 54 microns. There are many types of diamond powder, and the diamond powder produced by crushing, purification, grading and other processes using low-strength artificial diamond as raw material is the most common variety. This type of product covers the particle size range from tens of nanometers to tens of microns, and the products are cost-effective. Currently, they occupy most of the market share of diamond micropowder. With the continuous expansion of application fields, various types of diamond micropowders have appeared on the market according to different uses. 1. According to different sources of raw materials, it can be divided into natural diamond powder and artificial diamond powder. Low-grade natural diamonds that cannot be used in jewelry processing can be crushed by ball milling to produce diamond powder, which is used for industrial grinding and polishing, such as post-processing of gemstones and precision parts. With the rapid development of industry. The demand for diamond micropowder in the field of grinding and polishing has increased sharply, and the output of natural diamond micropowder is far from meeting the market demand. The emergence of artificial diamond has solved this problem, and it provides sufficient raw materials for diamond powder. Synthetic diamond powder is widely used in the grinding of hard and brittle materials. As a powder material, it can be used for grinding and polishing of various natural gemstones, artificial gemstones, glass, ceramics and other materials. Made into abrasive liquid and abrasive paste, it can be used for cutting, grinding and polishing of semiconductor materials such as silicon wafers, sapphire wafers and other components. It can also be made into a variety of products, such as precision grinding wheels, diamond composite sheets, fine grinding sheets, wire drawing dies, etc. It can be used in many fields such as geological drilling, optical glass processing, and wire production. 2. According to the strength of the raw material diamond, it can be divided into high-strength diamond powder and low-strength diamond powder. The former is a micropowder produced using high-strength diamond as a raw material. Micropowder has high single-particle strength, low internal impurity content and low magnetic properties. The latter uses low-strength diamond as the raw material. The product has good self-sharpening. 3. According to the diamond crystal structure, it can be divided into single crystal diamond powder and polycrystalline diamond powder (as shown in the figure below). Due to the large output and wide application fields of single crystal diamond powder, diamond powder is generally referred to as single crystal diamond powder in the industry. 1. According to the different diamond crystal structure, it can be divided into single crystal diamond powder and polycrystalline diamond powder (as shown in the figure below). Due to the large output and wide application fields of single crystal diamond powder, diamond powder is generally referred to as single crystal diamond powder in the industry. Single crystal diamond micropowder is produced by artificial diamond single crystal abrasive grains by static pressure method, after crushing and shaping treatment, it is produced by special process of superhard materials. Its particles retain the single crystal properties of single crystal diamond. It has a cleavage surface, and when it is impacted by an external force, it is preferentially broken along the cleavage surface, exposing a new "cutting edge". Polycrystalline diamond powder is a micron and submicron polycrystalline particle formed by diamond grains with a diameter of 5-10nm through unsaturated bonds, and the interior is isotropic and has no cleavage plane. Has high toughness. Due to its unique structural properties, it is often used in the grinding and polishing of semiconductor materials, precision ceramics, etc. In addition, there are nano-diamonds produced by the detonation method (as shown in the figure below). This type of diamond is synthesized from the excess carbon atoms inside the negative oxygen balance explosive under appropriate detonation conditions, and consists of diamond grains with a particle size of 5 to 20 nanometers. The secondary agglomerates composed of powders are generally gray-black in appearance. Nano-diamonds have good wear resistance, corrosion resistance and thermal conductivity. They can be used for precision polishing of hard disks and semiconductors, and can be used as lubricating oil additives to significantly improve lubrication. Lubricating properties of oil, reducing wear, can be added to rubber and plastic to enhance product performance, and can also be used as an excellent functional material to coat the surface of metal molds, tools, components, etc., to enhance surface hardness, wear resistance, and thermal conductivity. Extended service life. Two uses of diamond powder Diamond micropowder is widely used in machinery, aerospace, optical instruments, glass, ceramics, electronics, petroleum, geology, and military industry. It is an ideal material for grinding and polishing hard alloy ceramics, gemstones, and optical glass. Polycrystalline diamond micropowder utilizes good toughness, can maintain high grinding force and is not easy to scratch during the grinding and polishing process, and is widely used in the grinding and polishing of various hard materials such as optical crystals, ceramics, and superhard alloys. Generally, 0~0.5 micron diamond powder to 6~12 micron diamond powder is used for polishing; 10~15 micron to 22~36 micron is used for grinding; 12~22 micron is used for fine grinding. Three production process of diamond powder Diamond raw material→crushing and shaping→acid treatment→water washing→ultrasonic dispersion treatment→particle size classification→single particle size acid treatment→drying→particle size inspection→weighing, packaging and storage. Diamond micropowder is generally only produced with low-tech materials, which is what everyone calls the production of Class 1 materials. There are also some customized requirements and special applications, which will use three types of materials, such as diamond wire saws, glass drills and other electroplating products. 4. Grinding and Forming of Diamond Micropowder Crushing and forming are the key links in the production of diamond micropowder. The previous production process was mainly based on ball milling, which was mainly crushed, with moderate low-speed mechanical impact. It has been replaced by jet mill at present. The working principle of airflow grinding: compressed air is injected into the grinding chamber through the nozzle at high speed, and the diamond raw materials are repeatedly collided, rubbed and sheared at the intersection of multiple high-pressure airflows, and then crushed. The particles are crushed by high-speed collision, and the surface of the particles is crushed and formed by friction and shearing. Diamond micropowder is a superhard fine grinding and polishing material in the world today. In terms of its particle size, it belongs to micron, submicron and nanometer powders. Compared with coarse-grained powder, its specific surface area and specific surface functional groups are significantly increased, so the interaction force between particles is greatly increased during production. In addition, with the refinement of the particle size, the defects of the particle itself are reduced, and the strength is bound to increase. It can be seen that the production process of diamond micropowder is quite difficult. It is not only a process of particle refinement, but also accompanied by changes in crystal structure and surface physical and chemical properties. Therefore, the production process of diamond micropowder is a multidisciplinary engineering technology problem involving machinery, powder engineering, mechanics, physical chemistry, modern instruments and testing technology. With the development of cutting-edge technology and high-end manufacturing industry, the surface finish of many precision devices is very high, such as computer disk magnetic head optical communication devices, optical crystals, semiconductor substrates and other devices, all require precise polishing. Any bumps, scratches or attached foreign objects beyond the allowable range will not guarantee the accuracy and performance of the design. In short, with the efforts of our industry personnel, the manufacturing level of diamond micropowder in my country is improving year by year. Under the same material and equipment conditions, it has the highest cost performance in the world, but there is still a certain gap between the international high-end micropowder. The production of diamond micropowder is still There are many new problems that need to be overcome by colleagues, and this is also our future development goal and task.

A few days ago, Professor Jiashu, a professor at Saga University in Japan, cooperated with Orbray, a precision parts manufacturer in Japan, to develop a power semiconductor made of diamond and operate at a power of 875 megawatts (875,000 kilowatts) per square centimeter. This power semiconductor has the highest output power value in the world among existing diamond semiconductors. Compared with silicon carbide (SiC) products and gallium nitride (GaN) products, which are next-generation power semiconductors, diamond semiconductors have better performance such as high voltage resistance, and power loss is considered to be reduced to 1/50,000 of silicon products , At the same time, it is also very resistant to heat and radiation, so it is called the ultimate power semiconductor". The bandgap width of diamond is as high as 5.5eV, which is far higher than that of gallium nitride, silicon carbide and other materials. The carrier mobility is also three times that of silicon materials. The intrinsic carrier concentration is extremely low at room temperature, and it has excellent high temperature resistance properties . The application of diamond in the semiconductor field is becoming more and more extensive. Countries around the world are stepping up the research and development of diamond in the semiconductor field. Among them, Japan has successfully developed an ultra-high-purity 2-inch diamond wafer mass production method, and its storage capacity is equivalent to 1 billion Blu-rays. Optical disc (approximately 25 million TB). The annual output of natural diamonds in the world is about 150 million carats, while the output of synthetic diamonds exceeds 20 billion carats, 95% of which come from mainland China.

Diamond wire is made by uniformly consolidating diamond micropowder particles on the busbar (generally high-carbon steel wire) with a certain distribution density, and achieves the purpose of cutting through high-speed grinding motion between the diamond wire and the object to be cut. There are generally two manufacturing methods for diamond wire, that is, the cutting wire formed by fixing diamond particles on the wire by electroplating and resin. Strictly speaking, it is called diamond cutting wire, or diamond wire for short. The diamond wire has diamond micro-sawtooth, which increases the cutting ability of the steel wire, and can greatly speed up the cutting speed and cutting ability. 1. Diamond wire is mainly used in the photovoltaic industry The current mainstream process is electroplating diamond wire, which is to coat a layer of diamond powder on the metal wire to cut hard and brittle materials such as photovoltaic crystal silicon, crystal, magnetic materials, sapphire, etc. In recent years, diamond wire cutting technology has played an important role in the cutting industry. It plays an important role, and its application range is also extremely wide. It is mainly used in the current hot photovoltaic field, such as in the manufacture of silicon wafers, for cutting silicon rods, cutting squares, and slicing silicon wafers. The demand for silicon wafer cutting diamond wire accounts for more than 90% of the total demand. 2. Advantages of diamond wire Diamond wire was mainly used in the field of sapphire at the earliest, and it began to be applied in the photovoltaic field in 2015. Before photovoltaics were cut by mortar. When the Chinese people developed the mortar cutting technology to the extreme, there was no room for "cost reduction", and the diamond wire technology entered the field of vision of photovoltaic people. What are the advantages of diamond wire? 1. It can realize high-speed cutting. Compared with the traditional mortar cutting method, the speed is increased by 2-3 times, and the time-consuming is greatly reduced; 2. The traditional mortar cutting environment is harsh and not environmentally friendly, and a large amount of mortar needs to be recycled, which consumes a lot of manpower and financial costs. However, the diamond wire process does not require mortar, only water or water-based cooling cleaning fluid is needed. Yes, so diamond wire cutting has the advantages of environmentally friendly production and manufacturing; 3. The loss of silicon material is smaller than that of traditional cutting, and the overall cost of wire consumption is low; 4. The diameter of diamond wire can be adjusted, and different wire diameters are used for different materials, which greatly reduces the consumables and cutting accuracy; 5. Space saving, the diamond wire cutting machine occupies a small space, which can save a lot of space. 3. Technological innovation and challenges faced by diamond wire For the photovoltaic industry, reducing costs and increasing efficiency is an eternal topic, especially in the past two years when the price of silicon materials has soared and swallowed downstream profits. How to reduce cutting losses and reduce the cost of silicon wafers is an urgent need for silicon wafer companies to solve. 1. The inevitable result of silicon wafer thinning is the thinning of diamond wires Wafer thinning is the direction of the silicon wafer industry's efforts to reduce the cost of a single wafer in the past two years. Accompanied by the thinning of silicon wafers is the thinning of diamond wires. Advantages of thinning lines (1) Diamond wire thinning can reduce the loss of silicon during cutting. During the slicing process, the fragmentation rate of silicon wafers is reduced to improve the yield of silicon wafers. The high price of silicon material promotes the reduction of diamond wire diameter and reduces silicon consumption, which is the most direct and effective benefit. (2) After the diamond wire is thinned, it can cut thinner silicon wafers. It's like cutting vegetables with an ax and cutting vegetables with a kitchen knife. Both of these reasons help to cut the same length of silicon rod into a greater number of silicon wafers. (3) After the diamond wire is thinned, the amount of busbar material will be greatly reduced. As the diameter of the wire becomes smaller, the cross-sectional area becomes smaller, and the mass of the busbar becomes smaller, which shows that there is a saving in materials. Downsides of Thinning Lines (1) The thinner the wire, the more difficult it is to process the busbar drawing, nickel plating, and diamond powder application, and more cost is required; (2) The thinner the wire, the smaller the pulling force, the cutting speed and efficiency will be reduced, and time cost is required; (3) The thinner the wire, the smaller the diameter, and the smaller the amount of diamond powder attached to the same length. Cutting the same silicon wafer requires a longer diamond wire; (4) The thinner the wire, the easier it is to break under the same material, and the slicing process requires multiple wires to work together, and the wiring after the wire breaks takes a long time. 2. The busbar is facing the challenge of replacing the diamond wire itself and the tungsten wire itself. Although the cost of steel wire is lower than that of tungsten wire, the problem is that the breaking force is lower than that of tungsten wire, and the current 38-42 micron is close to the limit of steel wire. Tungsten wire substitution has become a new direction. Comparing steel wire and tungsten diamond wire from the perspective of service life, the usage times of tungsten diamond wire is 10-20 times that of steel wire. But the disadvantages are: first, the price of tungsten is higher than that of steel wire, and the price of tungsten wire of the same length is several times the price of steel wire; second, the winding length of tungsten wire is at most 100km, while steel wire can reach 300km, so transportation and use The cost is also higher than that of steel wire; third, the yield of the current tungsten wire busbar is lower than that of steel wire, thus increasing the cost of tungsten wire Therefore, there are both advantages and disadvantages of diamond wire thinning and busbar replacement, and trade-offs are required. From the perspective of historical development, the threshold for diamond wire is relatively low, which has also resulted in fierce competition for diamond wire for a period of time. At this point in time, we believe that the technology and production of diamond wires are being comprehensively improved. The development of wire thinning is accelerating, and at the same time, under the bottleneck of traditional high-carbon steel wire thinning, the busbar material is facing the possibility of replacement. Coupled with the continuous trend of large size and thinning of silicon wafers, the technical barriers of diamond wire are expected to be strengthened. In terms of production and manufacturing, leading enterprises have stepped up the transformation of one machine and multiple lines to greatly improve production efficiency. 4. Annual Demand Outlook for Diamond Wire The profitability of diamond lines in the photovoltaic industry chain is at the forefront. In 2021, the profit rate will be second only to silicon materials. The average gross profit rate will reach about 35%, and enterprises that extend upward to the busbar or further upstream can reach more than 50%. Thinning, thinning and large size are expected to increase the wire consumption of the slicing process. In terms of downstream demand, under the background of grid parity and carbon neutrality, the demand for photovoltaics has increased, and the expansion of superimposed silicon wafers has accelerated, making the demand for diamond wires expected to exceed industry growth. As the industry structure tends to stabilize, the price of diamond wire has gradually stabilized, and the thinner wire may bring a certain possibility of price increase. According to estimates, in 2021, the diamond wire consumed per GW will consume 340,000 kilometers, and in 2022, the diamond wire consumed per GW will reach 500,000 kilometers. It is estimated that by 2025, the market space for diamond wire in the photovoltaic field will reach more than 15 billion, and the compound growth rate will be more than 40% from 2021 to 2025.

Diamond wire is made by uniformly consolidating diamond micropowder particles on the busbar (generally high-carbon steel wire) with a certain distribution density, and achieves the purpose of cutting through high-speed grinding motion between the diamond wire and the object to be cut. There are generally two manufacturing methods for diamond wire, that is, the cutting wire formed by fixing diamond particles on the wire by electroplating and resin. Strictly speaking, it is called diamond cutting wire, or diamond wire for short. The diamond wire has diamond micro-sawtooth, which increases the cutting ability of the steel wire, and can greatly speed up the cutting speed and cutting ability. 1. Diamond wire is mainly used in the photovoltaic industry The current mainstream process is electroplating diamond wire, which is to coat a layer of diamond powder on the metal wire to cut hard and brittle materials such as photovoltaic crystal silicon, crystal, magnetic materials, sapphire, etc. In recent years, diamond wire cutting technology has played an important role in the cutting industry. It plays an important role, and its application range is also extremely wide. It is mainly used in the current hot photovoltaic field, such as in the manufacture of silicon wafers, for cutting silicon rods, cutting squares, and slicing silicon wafers. The demand for silicon wafer cutting diamond wire accounts for more than 90% of the total demand. 2. Advantages of diamond wire Diamond wire was mainly used in the field of sapphire at the earliest, and it began to be applied in the photovoltaic field in 2015. Before photovoltaics were cut by mortar. When the Chinese people developed the mortar cutting technology to the extreme, there was no room for "cost reduction", and the diamond wire technology entered the field of vision of photovoltaic people. What are the advantages of diamond wire? 1. It can realize high-speed cutting. Compared with the traditional mortar cutting method, the speed is increased by 2-3 times, and the time-consuming is greatly reduced; 2. The traditional mortar cutting environment is harsh and not environmentally friendly, and a large amount of mortar needs to be recycled, which consumes a lot of manpower and financial costs. However, the diamond wire process does not require mortar, only water or water-based cooling cleaning fluid is needed. Yes, so diamond wire cutting has the advantages of environmentally friendly production and manufacturing; 3. The loss of silicon material is smaller than that of traditional cutting, and the overall cost of wire consumption is low; 4. The diameter of diamond wire can be adjusted, and different wire diameters are used for different materials, which greatly reduces the consumables and cutting accuracy; 5. Space saving, the diamond wire cutting machine occupies a small space, which can save a lot of space. 3. Technological innovation and challenges faced by diamond wire For the photovoltaic industry, reducing costs and increasing efficiency is an eternal topic, especially in the past two years when the price of silicon materials has soared and swallowed downstream profits. How to reduce cutting losses and reduce the cost of silicon wafers is an urgent need for silicon wafer companies to solve. 1. The inevitable result of silicon wafer thinning is the thinning of diamond wires Wafer thinning is the direction of the silicon wafer industry's efforts to reduce the cost of a single wafer in the past two years. Accompanied by the thinning of silicon wafers is the thinning of diamond wires. Advantages of thinning lines (1) Diamond wire thinning can reduce the loss of silicon during cutting. During the slicing process, the fragmentation rate of silicon wafers is reduced to improve the yield of silicon wafers. The high price of silicon material promotes the reduction of diamond wire diameter and reduces silicon consumption, which is the most direct and effective benefit. (2) After the diamond wire is thinned, it can cut thinner silicon wafers. It's like cutting vegetables with an ax and cutting vegetables with a kitchen knife. Both of these reasons help to cut the same length of silicon rod into a greater number of silicon wafers. (3) After the diamond wire is thinned, the amount of busbar material will be greatly reduced. As the diameter of the wire becomes smaller, the cross-sectional area becomes smaller, and the mass of the busbar becomes smaller, which shows that there is a saving in materials. Downsides of Thinning Lines (1) The thinner the wire, the more difficult it is to process the busbar drawing, nickel plating, and diamond powder application, and more cost is required; (2) The thinner the wire, the smaller the pulling force, the cutting speed and efficiency will be reduced, and time cost is required; (3) The thinner the wire, the smaller the diameter, and the smaller the amount of diamond powder attached to the same length. Cutting the same silicon wafer requires a longer diamond wire; (4) The thinner the wire, the easier it is to break under the same material, and the slicing process requires multiple wires to work together, and the wiring after the wire breaks takes a long time. 2. The busbar is facing the challenge of replacing the diamond wire itself and the tungsten wire itself. Although the cost of steel wire is lower than that of tungsten wire, the problem is that the breaking force is lower than that of tungsten wire, and the current 38-42 micron is close to the limit of steel wire. Tungsten wire substitution has become a new direction. Comparing steel wire and tungsten diamond wire from the perspective of service life, the usage times of tungsten diamond wire is 10-20 times that of steel wire. But the disadvantages are: first, the price of tungsten is higher than that of steel wire, and the price of tungsten wire of the same length is several times the price of steel wire; second, the winding length of tungsten wire is at most 100km, while steel wire can reach 300km, so transportation and use The cost is also higher than that of steel wire; third, the yield of the current tungsten wire busbar is lower than that of steel wire, thus increasing the cost of tungsten wire Therefore, there are both advantages and disadvantages of diamond wire thinning and busbar replacement, and trade-offs are required. From the perspective of historical development, the threshold for diamond wire is relatively low, which has also resulted in fierce competition for diamond wire for a period of time. At this point in time, we believe that the technology and production of diamond wires are being comprehensively improved. The development of wire thinning is accelerating, and at the same time, under the bottleneck of traditional high-carbon steel wire thinning, the busbar material is facing the possibility of replacement. Coupled with the continuous trend of large size and thinning of silicon wafers, the technical barriers of diamond wire are expected to be strengthened. In terms of production and manufacturing, leading enterprises have stepped up the transformation of one machine and multiple lines to greatly improve production efficiency. 4. Annual Demand Outlook for Diamond Wire The profitability of diamond lines in the photovoltaic industry chain is at the forefront. In 2021, the profit rate will be second only to silicon materials. The average gross profit rate will reach about 35%, and enterprises that extend upward to the busbar or further upstream can reach more than 50%. Thinning, thinning and large size are expected to increase the wire consumption of the slicing process. In terms of downstream demand, under the background of grid parity and carbon neutrality, the demand for photovoltaics has increased, and the expansion of superimposed silicon wafers has accelerated, making the demand for diamond wires expected to exceed industry growth. As the industry structure tends to stabilize, the price of diamond wire has gradually stabilized, and the thinner wire may bring a certain possibility of price increase. According to estimates, in 2021, the diamond wire consumed per GW will consume 340,000 kilometers, and in 2022, the diamond wire consumed per GW will reach 500,000 kilometers. It is estimated that by 2025, the market space for diamond wire in the photovoltaic field will reach more than 15 billion, and the compound growth rate will be more than 40% from 2021 to 2025.

Diamond wire is made by uniformly consolidating diamond micropowder particles on the busbar (generally high-carbon steel wire) with a certain distribution density, and achieves the purpose of cutting through high-speed grinding motion between the diamond wire and the object to be cut. There are generally two manufacturing methods for diamond wire, that is, the cutting wire formed by fixing diamond particles on the wire by electroplating and resin. Strictly speaking, it is called diamond cutting wire, or diamond wire for short. The diamond wire has diamond micro-sawtooth, which increases the cutting ability of the steel wire, and can greatly speed up the cutting speed and cutting ability. 1. Diamond wire is mainly used in the photovoltaic industry The current mainstream process is electroplating diamond wire, which is to coat a layer of diamond powder on the metal wire to cut hard and brittle materials such as photovoltaic crystal silicon, crystal, magnetic materials, sapphire, etc. In recent years, diamond wire cutting technology has played an important role in the cutting industry. It plays an important role, and its application range is also extremely wide. It is mainly used in the current hot photovoltaic field, such as in the manufacture of silicon wafers, for cutting silicon rods, cutting squares, and slicing silicon wafers. The demand for silicon wafer cutting diamond wire accounts for more than 90% of the total demand. 2. Advantages of diamond wire Diamond wire was mainly used in the field of sapphire at the earliest, and it began to be applied in the photovoltaic field in 2015. Before photovoltaics were cut by mortar. When the Chinese people developed the mortar cutting technology to the extreme, there was no room for "cost reduction", and the diamond wire technology entered the field of vision of photovoltaic people. What are the advantages of diamond wire? 1. It can realize high-speed cutting. Compared with the traditional mortar cutting method, the speed is increased by 2-3 times, and the time-consuming is greatly reduced; 2. The traditional mortar cutting environment is harsh and not environmentally friendly, and a large amount of mortar needs to be recycled, which consumes a lot of manpower and financial costs. However, the diamond wire process does not require mortar, only water or water-based cooling cleaning fluid is needed. Yes, so diamond wire cutting has the advantages of environmentally friendly production and manufacturing; 3. The loss of silicon material is smaller than that of traditional cutting, and the overall cost of wire consumption is low; 4. The diameter of diamond wire can be adjusted, and different wire diameters are used for different materials, which greatly reduces the consumables and cutting accuracy; 5. Space saving, the diamond wire cutting machine occupies a small space, which can save a lot of space. 3. Technological innovation and challenges faced by diamond wire For the photovoltaic industry, reducing costs and increasing efficiency is an eternal topic, especially in the past two years when the price of silicon materials has soared and swallowed downstream profits. How to reduce cutting losses and reduce the cost of silicon wafers is an urgent need for silicon wafer companies to solve. 1. The inevitable result of silicon wafer thinning is the thinning of diamond wires Wafer thinning is the direction of the silicon wafer industry's efforts to reduce the cost of a single wafer in the past two years. Accompanied by the thinning of silicon wafers is the thinning of diamond wires. Advantages of thinning lines (1) Diamond wire thinning can reduce the loss of silicon during cutting. During the slicing process, the fragmentation rate of silicon wafers is reduced to improve the yield of silicon wafers. The high price of silicon material promotes the reduction of diamond wire diameter and reduces silicon consumption, which is the most direct and effective benefit. (2) After the diamond wire is thinned, it can cut thinner silicon wafers. It's like cutting vegetables with an ax and cutting vegetables with a kitchen knife. Both of these reasons help to cut the same length of silicon rod into a greater number of silicon wafers. (3) After the diamond wire is thinned, the amount of busbar material will be greatly reduced. As the diameter of the wire becomes smaller, the cross-sectional area becomes smaller, and the mass of the busbar becomes smaller, which shows that there is a saving in materials. Downsides of Thinning Lines (1) The thinner the wire, the more difficult it is to process the busbar drawing, nickel plating, and diamond powder application, and more cost is required; (2) The thinner the wire, the smaller the pulling force, the cutting speed and efficiency will be reduced, and time cost is required; (3) The thinner the wire, the smaller the diameter, and the smaller the amount of diamond powder attached to the same length. Cutting the same silicon wafer requires a longer diamond wire; (4) The thinner the wire, the easier it is to break under the same material, and the slicing process requires multiple wires to work together, and the wiring after the wire breaks takes a long time. 2. The busbar is facing the challenge of replacing the diamond wire itself and the tungsten wire itself. Although the cost of steel wire is lower than that of tungsten wire, the problem is that the breaking force is lower than that of tungsten wire, and the current 38-42 micron is close to the limit of steel wire. Tungsten wire substitution has become a new direction. Comparing steel wire and tungsten diamond wire from the perspective of service life, the usage times of tungsten diamond wire is 10-20 times that of steel wire. But the disadvantages are: first, the price of tungsten is higher than that of steel wire, and the price of tungsten wire of the same length is several times the price of steel wire; second, the winding length of tungsten wire is at most 100km, while steel wire can reach 300km, so transportation and use The cost is also higher than that of steel wire; third, the yield of the current tungsten wire busbar is lower than that of steel wire, thus increasing the cost of tungsten wire Therefore, there are both advantages and disadvantages of diamond wire thinning and busbar replacement, and trade-offs are required. From the perspective of historical development, the threshold for diamond wire is relatively low, which has also resulted in fierce competition for diamond wire for a period of time. At this point in time, we believe that the technology and production of diamond wires are being comprehensively improved. The development of wire thinning is accelerating, and at the same time, under the bottleneck of traditional high-carbon steel wire thinning, the busbar material is facing the possibility of replacement. Coupled with the continuous trend of large size and thinning of silicon wafers, the technical barriers of diamond wire are expected to be strengthened. In terms of production and manufacturing, leading enterprises have stepped up the transformation of one machine and multiple lines to greatly improve production efficiency. 4. Annual Demand Outlook for Diamond Wire The profitability of diamond lines in the photovoltaic industry chain is at the forefront. In 2021, the profit rate will be second only to silicon materials. The average gross profit rate will reach about 35%, and enterprises that extend upward to the busbar or further upstream can reach more than 50%. Thinning, thinning and large size are expected to increase the wire consumption of the slicing process. In terms of downstream demand, under the background of grid parity and carbon neutrality, the demand for photovoltaics has increased, and the expansion of superimposed silicon wafers has accelerated, making the demand for diamond wires expected to exceed industry growth. As the industry structure tends to stabilize, the price of diamond wire has gradually stabilized, and the thinner wire may bring a certain possibility of price increase. According to estimates, in 2021, the diamond wire consumed per GW will consume 340,000 kilometers, and in 2022, the diamond wire consumed per GW will reach 500,000 kilometers. It is estimated that by 2025, the market space for diamond wire in the photovoltaic field will reach more than 15 billion, and the compound growth rate will be more than 40% from 2021 to 2025.

The polycrystalline diamond compact drill bit is a composite sheet with a circular shape that is inlaid and welded on a cylindrical cutting tool, and the cutting tool is mounted on the drill body to become a PDC drill. Polycrystalline diamond compact drill bits are mainly divided into three categories 1. Composite drill bits for geological exploration The composite drill bit is mainly used for geological exploration and exploration, and is suitable for soft to medium-hard rock formations. Now some manufacturers have newly developed a new type of composite drill bit that can be applied to rock formations with ten grades of hardness. 2. Coalfield drilling adopts composite drill bit It is mainly used for drilling and mining of upper coal seams in coal mines. Generally speaking, the rock formations of coal fields are relatively soft, and composite drill bits are widely used, such as anchor drill bits, three-wing drill bits, etc. 3. Composite drill bits for oil exploration Drill bits are mainly used in drilling in oil and gas fields. At present, the composite drill bit for oil field is the most expensive and demanding among all the composite drill bits.

The key technology of diamond grinding wheel production lies in the bond formula and manufacturing process. In response to different customers, different processed materials, equipment, processing technology and precision requirements, diamond grinding wheels need to have different performances, which makes the customization of diamond grinding wheels higher. The performance of the grinding wheel bond, the type and concentration of diamond, and the process of key processes all directly affect the cutting efficiency, service life, and processing quality of the diamond grinding wheel. Generally speaking, the development trend of diamond grinding wheels is to realize precise, efficient and environmentally friendly processing of downstream materials. This requires strengthening the research on the performance of different types of diamonds, strengthening the research on the performance of the binder and the matching of specific types of diamonds, and strengthening the research on the processing accuracy requirements in different application fields.

The full name of PCD compact is polycrystalline diamond compact (PDC), which is subdivided into two types according to its application: oil field drilling and cutting tools. In order to better distinguish between the two, polycrystalline diamond compacts for oil field drilling are usually referred to as PDC for short, and polycrystalline diamond compacts for cutting tools are referred to as PCD compacts for short. PCD composite sheet is a composite material sintered with diamond micropowder and cemented carbide substrate under ultra-high pressure and high temperature (above 5.5GPa, above 1500°C). This material not only has the high hardness and high wear resistance of diamond At the same time, it also has the characteristics of toughness and weldability of cemented carbide. It is an ideal material for manufacturing cutting tools, drilling bits and other wear-resistant tools. my country successfully synthesized PDC for the first time in 1987 on a domestic six-sided top press, and applied it in the field of drilling. With the improvement of equipment, materials, and processes, it was only in 2003 that the domestic PCD compound for cutting tools was officially launched. Since then, the quality of PCD composite sheets in my country has been continuously improved, and the output and quality have made great progress in recent years. 1. Performance characteristics of PCD composite sheets for cutting tools (1) Compared with large single crystal diamond, PCD composite sheet as tool material has the following advantages: ①The crystal grains are arranged in disorder, isotropic, and have no cleavage plane, so it is not like the large single crystal diamond that has great differences in strength, hardness and wear resistance on different crystal planes, and because of the cleavage plane The presence of brittleness. ②It has high strength, especially the PDC material has high impact strength due to the support of the cemented carbide matrix. When the impact is large, only small grains will be broken, not as large as single crystal diamond. Block collapse, so PCD or PDC tools can not only be used for precision cutting and ordinary semi-precision machining, but also for rough machining and intermittent machining (such as milling, etc.) with a large amount of cutting, which greatly expands the diamond tool The scope of use of the material. ③ It can prepare large pieces of PDC diamond composite sheet tool blanks to meet the needs of large-scale processing tools such as milling cutters. ④ It can be made into a specific shape to meet the needs of different processing. Due to the enlargement of PDC tools and the improvement of processing technologies such as electric discharge and laser cutting technology, triangular, herringbone and other special-shaped knife blanks can be processed and formed. In order to meet the needs of special cutting tools, it can also be designed as wrap-type, sandwich-type and roll-type PDC tool blanks. ⑤The performance of the product can be designed or predicted, and the product can be given the necessary characteristics to adapt to its specific use. For example, choosing a fine-grained PDC tool material can improve the quality of the cutting edge of the tool, and a coarse-grained PDC tool material can improve the durability of the tool, and so on. (2) The performance and cutting characteristics of PCD composite sheet as a cutting tool are as follows: ①The hardness of PCD is high, second only to natural diamond, and its hardness and wear resistance are isotropic, that is, various physical properties are consistent in all directions. ②It has extremely high wear resistance, and its wear resistance is generally 60~80 times that of cemented carbide. ③It has a low coefficient of friction. Therefore, when processing the same material with the same processing parameters, the use of PCD tools can significantly reduce the cutting force and temperature. At the same time, due to the reduction of the coefficient of friction, the surface finish of the workpiece is also greatly improved. improve. ④It has high thermal conductivity, which is 1.5~7 times that of cemented carbide, which can greatly reduce the temperature in the cutting area and improve the durability of the tool. ⑤The linear expansion coefficient of diamond is very small, so the machining accuracy is good. 2. Application fields of PCD composite sheets for cutting tools Polycrystalline diamond composite sheet is also a new type of composite superhard material. It is a product that has been repeatedly mentioned in the "New Material Industry "14th Five-Year Plan" Development Plan", and has become the core component of high-end machine tool processing and is widely used. In aerospace industry, bearing industry, automobile processing and many other fields. According to statistics, the current market size of polycrystalline diamond composite sheets exceeds 30 billion yuan. With rapid development, the demand for domestic PCD composite sheets will increase at an annual rate of about 20%. With the progress of research on PCD composite cutting tool materials, its application has rapidly expanded to many manufacturing industries, such as aluminum and aluminum alloys, copper and copper alloys, hard alloys, engineering ceramics, graphite, plastics, rubber, laminates, silicon Rubber, Babbitt alloy, various composite materials, FRP, etc. Especially in automobile manufacturing, aerospace, aviation, shipbuilding and engine manufacturing industries, it can be widely used. With the continuous improvement of the new generation of large-scale six-sided roof devices and the continuous expansion of the synthesis chamber, the PCD composite sheet material is developing in the direction of large-scale size and continuous optimization of quality. The increase in size and specification of PCD composite sheets is an inevitable product of the development of ultra-high pressure and high temperature technology, and the continuous expansion of the synthesis cavity has created necessary conditions for the manufacture of large-diameter PCD composite tool materials.