Green Silicon Carbide and Black Silicon Carbide: Depth Differences Beyond Color

In the vast field of industrial materials, green silicon carbide and black silicon carbide are often compared. Both are important abrasives made by high-temperature smelting of raw materials such as quartz sand and petroleum coke in a resistance furnace, but their differences go far beyond the color differences on the surface. From subtle differences in raw materials, to significant disparities in performance characteristics, to vast differences in application scenarios, these differences together shape their unique roles in the industrial field.

 

 

1 The difference in raw material purity and crystal structure determines their distinct characteristics.

• Green silicon carbide is mainly made of petroleum coke and quartz sand, refined with the addition of salt. Through this process, the impurity content is minimized to the greatest extent possible, and the crystal structure is regular hexagonal with sharp edges. The processing of black silicon carbide raw materials is relatively simple, without adding salt. The residual impurities such as iron and silicon in the raw materials make the crystal particle shape irregular and rounded.

 

2 The differences in raw materials and structure result in different physical properties between the two.

• In terms of hardness, the Mohs hardness of green silicon carbide is about 9.5, second only to diamond, and it can process high hardness materials; Black silicon carbide is about 9.0, with slightly lower hardness. In terms of density, green silicon carbide has a density of 3.20-3.25g/cm ³ and a dense structure; Black silicon carbide 3.10-3.15 g/cm ³, relatively loose. In terms of performance, green silicon carbide has high purity, good thermal conductivity, conductivity, and high temperature resistance, but it is brittle and prone to breaking into new edges and corners; Black silicon carbide has slightly weaker thermal and electrical conductivity, lower brittleness, and stronger particle impact resistance.

 

3 The performance difference determines the application focus of the two.

• Green silicon carbide has high hardness and sharp particles, and is skilled in processing materials with high hardness and low toughness. In non-metallic fields, it can be used for glass polishing, ceramic cutting, and polishing semiconductor silicon wafers and sapphires; In metal processing, it performs well in high-precision machining of materials such as hard alloys and quenched steel, and is widely used in products such as grinding wheels and cutting blades. Black silicon carbide is mainly used for processing low hardness and high toughness materials, suitable for processing non-ferrous metals such as cast iron, copper, aluminum, and refractory materials. It has become a commonly used industrial choice in rough scenarios such as casting deburring and steel rust removal due to its high cost-effectiveness.

 

Although green silicon carbide and black silicon carbide belong to the same silicon carbide material system, there are significant differences in their physical and chemical properties and application characteristics. With the continuous innovation of materials science and processing technology, green silicon carbide and black silicon carbide are expected to achieve wider application expansion in high-tech fields such as semiconductor manufacturing, precision grinding, and new energy, providing key material support for the high-quality development of modern industry.