The present study relates to a method of making Al alloy / metal oxide metal matrix composites. The method involves injection of air bubbles to molten Al melt and vigorous agitation of the melt under oxygen-containing atmosphere, followed by degassing of the melt and casting them into a permanent mould. Alternately, additions of active elements, such as Ca, can be incorporated in the process to assist the formation of oxides under ambient atmosphere and the mixing of the oxides into the molten alloy. The formation of the oxides dispersed in the MMCs is the prime concerns in this process. The morphologies of the oxides formed in this process were examined by OM and EPMA/SEI. The effects of processing temperature and time, and the Ca content on the amount of oxide formed and on the wear resistance of the MMCs were also investigated.
Metal matrix composite air bubble Molten al Oxides Agitation