Microstructure and Properties of C/Cu-Cr Self-lubricating Composite Prepared by Hot-pressing Sintering

C/Cu-Cr composite material was prepared by hot-pressing sintering with Cu-Cr alloy powders obtained from mechanical alloying.The microstructure and properties of the composite material were emphatically analyzed.The results show that with Cr content increasing,both relative density and conductivity of the composite material gradually decrease,and its hardness increases,and bending strength increases first and then decreases.When Cr content is 1%,the bending strength reaches a maximum.The composite material with 1%Cr and 2%C has relative density of 98.82%,conductivity of 85.57%IACS,hardness of HBS 69.34,and bending strength of 330 MPa.Compared with conventional cold-pressing sintering,hot-pressing sintering can obtain a composite material of finer crystal grain,more uniform reinforcing phase distribution and more excellent comprehensive performance.