Pure silicon carbide powder is a colorless, transparent crystal. Industrial silicon carbide is light yellow, green, blue or even black due to the type and content of impurities contained in it. The transparency varies with its purity. The crystal structure of silicon carbide is divided into hexagonal or rhombohedral α-SiC and cubic β-SiC (called cubic silicon carbide). Since α-SiC constitutes many different variants due to the different stacking sequences of carbon and silicon atoms in its crystal structure, more than 70 kinds have been found. β-SiC is converted to α-SiC at 2100 ° C or higher. The industrial production method of silicon carbide is refined in a resistance furnace using high-quality quartz sand and petroleum coke. The obtained silicon carbide block is made into various particle size products by crushing, acid-base washing, magnetic separation, screening or water selection.
Alpha Sic and Beta Sic have the following differences:
1. In the synthesis process, the synthesis temperature of Beta sic is about 1500-1600 °C, and the smelting temperature of Alpha sic needs to exceed 2400 °C. Since the Beta sic smelting temperature is much lower than Alpha sic, its sintering activity is better, the particles are easier to refine and homogenize, and a large number of nano, submicron and micron ultrafine particles can be produced.
2. The crystal form of Beta sic is cubic, spheroidal, and the equiaxed structure of the crystal determines that the powder has better natural sphericity and self-sharpness than a-sic, so it has better grinding in precision grinding. The cutting and polishing effect has better sealing properties in the production of materials, sealing products and military products, so that the products have better density. Alpha sic is a hexahedron.
2. The crystal form of Beta sic is cubic, spheroidal, and the equiaxed structure of the crystal determines that the powder has better natural sphericity and self-sharpness than a-sic, so it has better grinding in precision grinding. The cutting and polishing effect has better sealing properties in the production of materials, sealing products and military products, so that the products have better density. Alpha sic is a hexahedron.
3. The hardness of Beta sic is much higher than that of Alpha sic. Therefore, Beta sic has better performance and much higher grinding efficiency when grinding. It is generally used in the field of superfine grinding.
4. Abrasives: Alpha sic can be used for rough polishing. In polishing, Beta sic is used to improve the finish. Polished with diamond, the price is about 10 times that of beta sic, so Beta sic products have high grinding precision and good finish, which is not suitable for scratching, and the performance is more prominent in fine grinding.
5. beta sic has better electrical properties than alpha sic and higher purity in preparation, making it more unique in the field of electrical materials, especially in the field of semiconductors. It is several times better than Alpha sic in terms of conduction and heat conduction. It can be used as a heater, heat exchanger and electric heater. It has good thermal shock resistance and is not afraid of cold and heat. Other materials are much less effective.
6. Cubic silicon carbide, also known as Beta sic, is a cubic crystal system. The Beta sic hardness is 9.25--9.6, which is close to the diamond 10 and has a better finish than diamond. Beta sic is one of the hardest high-performance materials after steel. Its ultra-high hardness and density make it ideal for parts subject to high wear and sliding wear. It is suitable for all kinds of grinding, especially ultra-precision. Grinding; Beta sic is a low temperature crystal form, and crystal form conversion can occur at 1800 °C. Beta sic has ultra-high strength and excellent creep and fracture resistance at temperatures up to 1600 ° C (3000 ° C). As a semi-conductive material, Beta sic is several times higher than Alpha sic. After addition, the generator material will be better and the temperature is better. The Beta sic is half the weight of most alloys, just 40% of the alloy. the same.
beta sic (cubic silicon carbide powder) is the main product of SAT NANO, including 50nm, 100nm, 0.5um, 1 micron, 5 micron, 10 micron. The purity is 99%. Welcome to ask us a quote.
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