The Microstructure and Mechanical Properties of SiCp-reinforced Copper Matrix Composites by Hot Pressing

摘要

SiCp-reinforced copper matrix composites with the reinforcement content of 30-50 vol.% were fabricated by hot pressing using Cu-coated and uncoated SiC powder. The microstructure and mechanical properties of the composites were studied. The results showed that with the increasing of SiCp volume fraction, the Brinell hardness of the composites increased first and arrived at a peak value, then decreased, while the bending strength decreased continuously. On the condition of same volume fraction of SiCp, the Brinell hardness and bending strength of the composites using coated powder were higher than that of the composites using uncoated powder. The annealing treatment lowered the Brinell hardness and bending strength of the composites. When the volume fraction of SiCp was 30 vol.%, the fracture mechanism of the composites showed a mixed manner of dimple and quasi-cleavage fracture. While the volume fraction of SiCp was 50 vol.%, the fracture behavior of the composites dominated in quasi-cleavage manner with seldom dimples.