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Super hard materials refer to the material comparable to diamond. The current ultra -hard materials used are mainly cubic boron nitride and diamond, but many super-hard materials are under development, such as boron carbide, boron -rich oxide, etc. Diamond, including natural diamonds and artificial diamonds, natural diamonds are currently the hardest industrial materials in the world. It has the characteristics of high hardness, high abrasion resistance, and good thermal stability. The heat dissipation materials, semiconductor chips, etc. have been widely used in metallurgical, petroleum drilling, construction engineering, mechanical processing, electronics industry, aerospace and modern cutting-edge science. Cube boron nitride CBN is the material of hardness second only to diamond, but no natural cubic boron nitride is not found at present, and artificially used in industry and daily life. It has the characteristics of many characteristics of diamond, and also has higher thermal stability and chemical inertia for iron metals and its alloy. As an engineering material, it has been widely used in black metal and its alloy material processing industry. At the same time, it has excellent performance, electrical, optical, and acoustic performance. It is applied in a series of high-tech fields and has become a functional material with development prospects.

The performance of super hard materials:

Structural composition: diamondis the carbon atom to connect to each other by the tetrahedron to form an unlimited three -dimensional skeleton, which is a typical atomic crystal. Each carbon atom is used to form a co -price bond with the other four carbon atoms to form a positive tetraonal body. Because the C-C key is very strong, all the price electrons are involved in the formation of the common price bond. There is no free electrons. Therefore, the diamonds are not only hard, high, but also non-conductive. Boron nitride is a cubic structure.

Mechanical properties: King Kong is the hardest material on the earth, Mo’s hardness is 10. New Mo’s hardness 15, microscopic hardness 10000kg/mm. The hardness of the eight -sided crystal surface is greater than the hardness of the diamond-shaped dose-as-on-surface crystal surface. Diamondhas a great elastic modulus and is a grinding material in nature, with an elastic modulus of 90,000kg/mm. The friction coefficient is small and has a very high abrasion ability. Therefore, this feature is used in diamond ore, and the ball mill and tapered grinding miners are used to separate diamonds. But diamonds are extremely crispy and cannot withstand positive external impacts. High hardness and good abrasion resistance.

Thermal science performance: melting point: diamondmelting point is 4000 ° C, the burning temperature in the air is 850 ~ 1000 ° C, burned at 720 ~ 800 ° C in pure oxygen, a light blue flame was emitted, and it was converted into carbon dioxide. However, the thermal conductivity of Type IIA diamonds is particularly high. It is 25 times that of copper at the temperature of liquid nitrogen, and it has decreased sharply with the increase in temperature. At low temperature, the thermal expansion coefficient is very small. With the increase in temperature, the thermal expansion coefficient increases rapidly. Cube boron nitride began to transform from cubic crystal to hexagonal crystals above 1370º or more; cutting at a high temperature of 1000ºC, the surface of its surface will not produce oxidation, and the degree of reduction in hardness at high temperature is much smaller than hard alloy and ceramic blade. Conditions are created for high-speed cutting. The thermal conductivity is 79.54W/m, K, second only to diamond. With the temperature increase, the thermal conductivity is gradually increased, which is conducive to heat dissipation.

Magnetic performance: diamonds are unspeakable and heavy-duty minerals. Therefore, electromagnetic selection (neutral and weak magnetic) methods cannot be used in the mineral selection. In some cases, a certain magnetism is displayed because it contains a magnetic parcel.

Optical properties: Polariticity: Most diamonds are displayed in non-equalization under polarizing, and diamonds and other axis -based minerals should be theoretically average, but it is formed by diamond in the geological body with stress changes. Due to stress stress, due to stress stress, it is due to stress stress. The role of diamond crystal has a local dislocation, so it shows uneven non-average quality.

Application of super hard materials

• Compared with ordinary abrasive gear, CBN grinding tool CBN grinding gear has a sharp sharpener, good wear resistance, high processing efficiency, excellent processing surface quality, high processing accuracy, long service life, low unit processing costs and energy saving.
• Long life, suitable for deep wells and grinding strata. In the case of high ground temperature, the bearing of the general drill is easy to fail, and the problem of using diamond material drills will not occur.
• Diamond cutting tools   The diamond sawing tool mainly refers to various types of diamond cutting saw blades, including round saw sheets, row saws, rope saws, etc. It is mainly used to cut non-metallic materials such as marble, granite and concrete.