Preparation of aluminium-zirconium master alloys

摘要

Preparation of Al-Zr master alloys was investigated by aluminothermic reduction of zirconium oxide (ZrO_2) using sulphur (S)-based sings. The influences of process variables such as requirement of beat energiser (KClO_3 + Al), amount of aluminium (Al) reductant, slag compositions, etc. were investigated to establish conditions for good slag-alloy separation and also to get optimum recoveries of the alloy. A maximum recovery of 92.8 percent Al-Zr alloy was obtained for a charge containing 20 percent excess aluminium over stoichiometric requirement, 50 g KClO_3, and 99 g S per 100 g ZrO_2. The alloy, on chemical analysis, was found to contain 33.74 wt percent Zr, 0.4 wt percent oxygen, 0.0035 wt percent nitrogen and 0.5 wt percent S.