Evaluation of HEBM Mechanical Alloying of Al 2 O 3 — 356/7075 Powder Mixture

Particle reinforced aluminium alloy metal matrix composites (MMC) have proven to be one of the advanced materials capable of replacing conventional structural alloys. However, the demand for such materials has been confined to high cost applications due to their complex processing. A preliminary mechanical alloying (MA) of metal powder with ce-ramic particulates by High Energy Ball Mill (HEBM) processing is a step of MMC manufacturing process. In this paper mechanical alloying of aluminium alloys A356 and 7075 powder with Al2O3 and SiC par-ticulates using two types of HEBM was investigated. The effect of dispersed phase strengthening mechanism on three aluminium grade alloys was evaluated by micro hardness measurement. Microstructure investigation confirms the achieved strengthening results. It was established that by measuring hardness of alloyed aluminium particles with low load reliable information on the alloying effect can be achieved.