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Black corundum is a grayish-black crystal in which Al2O3 and iron spinel are the main mineral phases; it is produced by melting high-alumina bauxite together with high-iron-alumina bauxite or iron oxide filings in an electric arc furnace at high temperatures, followed by cooling. Its main chemical components are aluminum oxide (Al2O3) and iron oxide (Fe2O3), with additional amounts of silicon dioxide (SiO2), titanium dioxide (TiO2), and other components. Next, let the editor from Chikka Shinai Material give you a detailed introduction! Since black corundum is a wear-resistant product manufactured through controlled processes, its consistent and optimal internal composition and crystal structure ensure relatively stable performance in practical use. Microscopically, corundum exhibits a grinding and polishing effect primarily due to aluminum oxide particles that are dispersed in a microcrystalline state, surrounded by silicon oxide of slightly lower strength, forming a structure similar to that of packed abrasives. Black corundum has the advantages of moderate hardness and toughness, good self-sharpening property, low grinding heat generated during grinding and polishing, and the ability to prevent scorching of the workpiece surface. The production cost of black corundum is lower than that of brown corundum and white corundum, and even lower than that of common abrasives such as calcined brown corundum and silicon carbide. Black corundum was initially used mainly for various stainless steel, ordinary steel, bamboo, wood, glass, and other workpieces, especially for the grinding and polishing of stainless steel parts. Over the past decade or so, the application of black corundum has expanded to areas such as the construction of wear-resistant and anti-slip road surfaces, the production of resin molds, and the manufacture of bonded grinding tools. Practical applications in recent years have shown that tools made from high-hardness and durable abrasives such as black corundum composite brown corundum, calcined brown corundum, silicon carbide, single-crystal corundum, zirconium corundum, and ceramic abrasives exhibit even superior performance!