Product Performance and Application Range of Black Corundum
Abrasives are indispensable processing materials in grinding, polishing and finishing processes. Due to the diversity of parts, there must be corresponding polishing abrasives and grinding tools. Abrasives can be divided into brown corundum, white corundum, black fused alumina, etc. according to different colors. Corundum abrasives were once known as "industrial teeth", which shows how important their role is in industrial applications!
black fused alumina, also known as low-aluminum corundum, is a gray-black crystal with aluminum oxide and iron spinel as the main mineral phases obtained by smelting bauxite in an electric furnace. Its melting point is at 2050℃,
It has moderate hardness, high toughness, self-sharpening, good adhesion, high durability, less heat generation during grinding, high temperature resistance, not easy to scratch the surface of the workpiece, and high surface finish of the workpiece.
black fused alumina is processed by electrofusion dry method, and the process flow is as follows: bauxite and other auxiliary materials--crushing--scientific proportioning--electrofusion smelting--semi-finished block--coarse crushing--sorting--fine crushing--segmented screening--magnetic separation--clearing and blowing--fine screening--inspection--packaging--export.
Laying Wear-Resistant and Anti-skid Pavement
black fused alumina segment sand is used for laying wear-resistant and anti-skid pavement, bridge deck, parking lot, sharp bends and steep slopes. It has good wear-resistant and anti-skid performance. The black fused alumina has a consistent matte black color inside and outside, which is particularly suitable for paving pavement and bridge deck floors. Compared with the original brown corundum and silicon carbide aggregate, it has a very high cost-effectiveness advantage. European countries, Hong Kong, and economically developed areas in China have been using it regularly for nearly ten years. The general usage in China is to use resin to bond one or more layers on the cement roadbed, and to use asphalt as a binder and black fused alumina as aggregate to pave the road surface, bridge deck or floor surface.
Free Grinding and Polishing
It is mostly used for polishing various metal parts before electroplating. The medium and fine black fused alumina grain sand was originally mainly used for sandblasting, grinding and polishing of various stainless steel, ordinary steel, bamboo, wood, glass and other workpieces, especially the surface treatment of stainless steel.
Making Resin Abrasives and Cutting Discs
In the past ten years, more than a dozen factories of internationally renowned abrasive tool groups around the world and many large resin abrasive tool manufacturing companies in China have added 30%-50% black fused alumina to high-hardness wear-resistant materials such as brown corundum or calcined brown corundum to make composite abrasives for the production of resin grinding wheels, resin cutting discs, resin grinding discs, resin ultra-thin sheets and other abrasives. The use of composite abrasives can improve the sharpness of the cutting disc, improve the smoothness of the cut, make the discoloration more minor, make the cutting machine more stable during operation, and have a high cost-effectiveness. It has now become the main application area of black fused alumina products.
Make Coated Abrasives
According to the characteristics of brown corundum and black fused alumina, the sandpaper made in different proportions is converted into sanding belts. After tens of thousands of sanding belt grinding tests, it is proved that the sanding belt made of black fused alumina and brown corundum composite abrasives is better than pure black fused alumina and pure brown corundum sanding belts in polishing stainless steel. This can not only greatly reduce the cost of raw materials, but also make the product performance more suitable for the processing object, make the grinding effect better, and have a higher cost performance.
Other Aspects
With the in-depth understanding of the characteristics of black fused alumina, its application field will be further expanded. black fused alumina can be used as an additive for wear-resistant and fire-retardant coatings; it can be used as polishing wax and polishing blocks for grinding and polishing; it can be used as wear-resistant aggregates and wear-resistant tools; it can be used to make jeans sandblasted and aged; it can be used to make amorphous refractory materials; it can be used to make gun mud for steelmaking furnaces, etc.
