Abstract: According to practical demand of a balanced Piston material used for valve seatand valve body of engine,several high temperature seflf-lubricating composites were preparedusing medium frequency hot press process with the super nickel alloy matrix,Ag and graphitelubricating phase and SiC hard particles dispersive phase. The physical-mechanical propertiesand friction-wear performances of the composites were systematically tested.A certain kind ofmaterial,which can be used to make valve seat and piston was selected,has been normally runfor 1 200 seconds at the engine specification conditions and itsvarious performances reach thedefined technical demands.