Effects of Processing Parameters on Properties of SiCp/Al Composites

The effects of hot pressing and hot extrusion temperatures on the properties of 12%SiCp/6066Al (volume fraction) composites fabricated by powder metallurgy have been studied. The experimental results indicate that the hot extrusion, an essential stage of powder metallurgy to produce this sort of particle reinforced metal matrix composites, can redistribute SiC particles in metal matrix and refine the matrix grain size, and that the hot pressing can improve the interfacial cohesion strength between SiC particles and metal matrix. When hot-pressed at temperatures slightly higher than the solidus temperature of the composite and hot-extruded at lower temperatures, the composites are stronger due to the high metal matrix strength and interfacial cohesion. The optimum parameters of hot pressing and hot extrusion in the composites are 560 and 430 °C, respectively.