Whiskers of A1_2O_3 as reinforcement of a powder metallurgical 6061 aluminium matrix composite

摘要

An Al-Mg-Si alloy matrix composite reinforced with 10 vol.% of alumina whiskers (Al_2O_3w) has been processed by powder metallurgy and investigated. The Al_2O_3w were produced as single crystal c-axis alpha-alumina fibres at pre-pilot scale via vapour-liquid-solid (VLS) deposition in a cold-wall air-tight furnace with alumina linings. As far as we know, this is the first report of the utilization of whiskers of A1_2O_3 as reinforcing elements for Al alloys. Tensile tests have been performed on the composite at room and high temperatures. Results show that the AA6061 alloy reinforced with the as-produced A1_2O_3 whiskers has remarkably high mechanical properties at room temperature. This is attributed to the high quality of the A1_2O_3 single crystals and to the strong bonding attained between them and the 6061 alloy matrix.