... and iron filings, smelting by high tempetures in electric spark furances. Brown fused aumina is the ... Si, Ti and so on. Its micro-hardness is HV 1800-2200. Its tenacity is higher than that ... coating.(2) Due to high hardness, wear resistance, high strength characteristics, in the chemical system, used for ... hollow ball and fiber products, widely used in a variety of high-temperature kiln furnace walls ...