Effect of cryolite on microstructure of insitu AlB2 aluminium metal matrix composites

Abstract

Todays composite material have gained more popularity due to their improved properties over the conventional materials. In the present paper, insitu composites were fabricated via chemical reaction between molten aluminium alloy and halide salt KBF4 with cryolite at 8000C by stir casting method. The microstructures of the composite containing 3 and 5 wt. % of AlB2 reinforcement phase have been compared with the unreinforced aluminium alloy. The microstructure analysis shows clean AlB2 particles uniformly distributed throughout the matrix. With the increase in the AlB2 reinforcement, insitu composite show less agglomeration and recovery of boron is more when compared to the unmixed halide salt in the fabrication of inistu composites.