Abstract
Al-(10-15)%B4C MMCs was produced using a powder injection technique (propriety to Universite du Quebec a Chicoutimi). Two base matrices were used: pure Al and 6063 alloy. Small amounts of Ti and Zr were added to each melt before B4C powder injection was carried out. Composite melts were poured into metallic L-shaped and rectangular book-type molds. As-cast microstructures revealed uniform distribution of B4C particulate and good wettability with the matrix. Segregation was sometimes observed when the melt was stirred at low speed. The added elements appeared as a necklace surrounding the B4C particles, preventing reaction with the matrix, as compared to a Metal Matrix Composite (MMC) with no additions, where Al-B or Al-B-C compounds were often observed. Some of the cast slabs were remelted to simulate recycling. The microstructure revealed excellent adherence between the B4C particles and the matrix. The slabs were successfully rolled down from 40 mm (1.6 in.) to 2 mm (0.08 in.) thick sheets using a special rolling pass design.