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　　以高純鋁礬土為原料，在電弧爐中熔融，加入還原劑和穩(wěn)定劑，延長結(jié)晶溫區(qū)，使晶體充分完整生長。和普通剛玉相比具有硬度高，強(qiáng)度高，鋒利度好等特點(diǎn)。
　　he high purity bauxite was used as raw material to melt in the electric arc furnace, the ucing agent and stabilizer were added to prolong the crystallization temperature zone and make the crystal grow fully and completely. Compared with common corundum, it has the characteristics of high hardness, high strength and good sharpness.