What is black silicon carbide?
Black silicon carbide, also called black SiC or black carborundum, is made of raw materials such as quartz sand, petroleum coke (or coal coke), and sawdust (salt is needed to produce green silicon carbide) through high-temperature smelting in a resistance furnace. It has high strength, high hardness, wear resistance, corrosion resistance, oxidation resistance, high thermal conductivity, good high-temperature stability, corrosion resistance, etc. Its characteristics and uses are as follows:
1. Physical and chemical properties
SiC ≥ 98%, presents a black metallic luster, and the crystal structure is mostly hexagonal (α-SiC).
Pure silicon carbide is a colorless and transparent crystal, and industrial black silicon carbide is black or dark blue due to impurities (such as iron, aluminum, etc.).
Mechanical properties
Black silicon carbide has a hardness between corundum and diamond (microhardness 2840~3320 kg/mm²), and its mechanical strength is higher than that of corundum, but it is more brittle.
Excellent wear resistance and thermal conductivity, low thermal expansion coefficient, and stable chemical properties at high temperatures.
2. Production standards and corresponding particle sizes under the standards
JIS standard: #14#16 #20 #24 #30 #36 #46 #54 #60 #70 #80 #90 #100 #120 #150 #180 #220 #240 #280 #320 #360 #400# #500 #600 #700 #800 #1000 #1200 #1500 #2000 #2500 #3000 #4000 #6000 #8000 #10000
FEPA standard: F14 F16 F20 F22 F24 F30 F36 F46 F54 F60 F70 F80 F90 F100 F150 F180 F220 F230 F240 F280 F320 F360 F400 F500 F600 F800 F1000 F1200 F1500 F2000
P standard: P12 P16 P20 P24 P30 P36 P40 P50 P60 P80 P100 P120 P150 P180 P220 P240 P280 P320 P360 P400 P500 P600 P800 P1000 P1200 P1500 P2000 P2500 P3000 P4000 P5000
3. Application areas
Abrasives and grinding tools
Manufacturing grinding wheels, sandpaper, oilstones, etc., suitable for grinding cast iron, non-metallic materials and cemented carbide.
High-purity micro powder is used for precision grinding and polishing of monocrystalline silicon and polycrystalline silicon.
Refractory materials
Used for high-temperature kiln linings, refractory bricks, etc., with excellent thermal shock resistance.
Functional materials
Apply to turbine blades or cylinder walls to improve wear resistance and extend life.
Used as high-temperature or high-frequency materials in semiconductors and electronic devices.
4. Differences from green silicon carbide
Composition and performance: Green silicon carbide contains SiC ≥ 98.5%, has higher hardness but lower brittleness, and is mainly used for grinding carbide tools; black silicon carbide has greater mechanical strength and is suitable for processing non-metals and cast iron.
Production process: Green silicon carbide requires the addition of salt as a reaction catalyst, while black silicon carbide does not require this step.
With its high hardness, high temperature resistance and chemical stability, black silicon carbide has become one of the core raw materials in the fields of abrasives, refractory and functional materials.
5. Market supply
Zhengzhou Haixu Abrasive Co., Ltd. is a major manufacturer of black silicon carbide, providing various types of black silicon carbide sand and black silicon carbide micropowder, with sufficient inventory and support for export-grade customization. Its conventional packaging is 25 kg plastic woven bag + ton bag/pallet wrapping.