Silicon carbide (SiC) ceramics exhibit exceptional properties, including high resistance to oxidation, strength at elevated temperatures, chemical stability, thermal shock resistance, thermal conductivity, and airtightness. As a result, SiC ceramics find wide application across diverse fields such as energy, metallurgy, machinery, petroleum, chemical industry, aviation, aerospace, and national defense.

Black & Green Silicon Carbide

Silicon carbide is commonly used in the abrasive industry and can be classified into two types based on color: black silicon carbide and green silicon carbide. Both types exhibit hexagonal crystal structure.

Black silicon carbide typically consists of 98.5% SiC and is primarily derived from high-quality silica, quartz sand, and petroleum coke. This type of silicon carbide is produced by smelting the raw materials in a resistance furnace at high temperatures. It exhibits greater toughness than green silicon carbide and is predominantly used for processing materials with low tensile strength, including glass, ceramics, stone, refractory materials, cast iron, and non-ferrous metals.

Green silicon carbide, with a silicon carbide content of over 99%, is produced by smelting petroleum coke and high-quality silica in a resistance furnace at high temperatures. During the smelting process, salt is added as an additive. This type of silicon carbide is known for its self-sharpening properties and is typically used for processing hard alloy, chrome steel, optical glass, as well as for wear-resistant cylinder sleeves and precision grinding of high-speed steel cutters.

Silicon Carbide vs. Other Ceramics

Silicon carbide ceramics stand out as the most superior option among other new types of ceramics due to their excellent properties. Although alumina (Al2O3) ceramics are widely used because of their low sintering temperature, low cost, and good electrical insulation, their application in high-power circuits is limited due to their low thermal conductivity. On the other hand, beryllium oxide (BeO) ceramics ceramics have good comprehensive dielectric properties and are used as highly thermally conductive substrates in some fields. However, regulations have been issued in Europe, America, Japan, and other places to restrict the sales and research and development of electronic products containing BeO due to its toxicity.

Aluminum nitride (AlN) ceramic is another type of ceramic that exhibits excellent thermal conductivity, electrical insulation, and low dielectric constant, making it suitable for high-power circuits. However, the high sintering temperature of AlN ceramics results in a complex preparation process and high cost, which has prevented its large-scale production and application. In comparison, silicon carbide ceramics have many advantages, such as low density, high mechanical strength, good oxidation resistance, wear resistance, excellent thermal shock resistance, and low thermal expansion coefficient, etc. It has good development and application prospects in the field of electronic products, which can meet the requirements of high performance, small lightweight, and high reliability of electronic equipment in the future.

Conclusion

Silicon carbide ceramics offer exceptional properties such as high resistance to oxidation, thermal conductivity, thermal shock resistance, and airtightness. Compared to other ceramics, silicon carbide ceramics have many advantages, making them suitable for electronic products that require high performance, small size, and high reliability.

Advanced Ceramic Materials (ACM) supplies high-quality silicon carbide & other types of ceramic materials to meet our customers’ R&D and production needs. Please visit https://www.preciseceramic.com/ for more information.