Fabrication and characterization of Copper/Silicon Nitride composites

. Copper/silicon nitride (Cu/Si 3 N 4 ) composites are fabricated by powder technology process. Copper is used as metal matrix and very fine Si 3 N 4 particles (less than 1 micron) as reinforcement material. The investigated powder were used to prepare homogenous (Cu/Si 3 N 4 ) composite mixtures with different Si 3 N 4 weight percentage (2, 4, 6, 8 and10). The produced mixtures were cold pressed and sintered at different temperatures (850, 950, 1000, 1050 ° C). The microstructure and the chemical composition of the produced Cu/Si 3 N 4 composites were investigated by (SEM) and XRD. It was observed that the Si 3 N 4 particles were homogeneously distributed in the Cu matrix. The density, electrical conductivity and coefficient of thermal expansion of the produced Cu/Si 3 N 4 composites were measured. The relative green density, sintered density, electrical conductivity as well as coefficient of thermal expansion were decreased by increasing the reinforcement phase (Si 3 N 4 ) content in the copper matrix. It is also founded that the sintered density and electrical conductivity of the Cu/Si 3 N 4 composites were increased by increase the sintering temperature.