Al₂O₃/Al particle-reinforced aluminum matrix composite by displacement reaction

The development of a novel Al matrix composite is described based on a simple displacement reaction when an SiO₂ particulate preform is brought into contact with liquid Al at temperatures between 1273 and 1373 K. This interaction leads to the wetting of the SiO₂ particles by Al and its eventual transformation to a composite with Al₂O₃/Al particles in an Al matrix. Infiltration of the preform as induced by this reaction takes place with the simultaneous formation of the Al₂O₃/Al particles in situ. Synthesis of engineered multiphase composites, wherein reinforcements of other materials incorporated into the preform and reacted with liquid Al, is also presented.