Properties and microstructures of 7075/SiCp composites prepared by spray deposition

The 7075/SiCp composites were prepared by spray deposition, extrusion and heat treatment technologies. The microstructures of the deposit, the extruded and heat-treated bars were analyzed. And the mechanical properties and wearing resistance were tested and compared with other aluminum alloys. The results show that the spray deposited preform presents fine microstructure and uniformly distributed SiC particles. Compared with the matrix alloy, the yield strength, modulus and wearing resistance of the peak-aged composites are improved markedly with 50% reduction of elongation. It indicates that the addition of SiC particles greatly contributes to the refining of microstructure and the altering of fracture and wearing mechanisms.