Preparation and characterization of copper/copper coated silicon carbide composites

Abstract

In this study, a thin layer of copper was deposited homogeneous on SiC particles by using the electroless coating technique. SiC reinforcement particle coated with thin layer of copper film was then blended with copper to produce Cu/SiC composite. The Cu matrix and SiC reinforcement (both Cu-coated and non-coated) was first mixed via ball milling method and pressed in a customized mold with 50 kN uniaxial compaction load. The compacted samples were then sintered at 925°C for 2 hours in argon atmosphere. The SEM image showed the deposition of copper layer on SiC particle surface after the coating process. XRD analysis proves the existence of both Cu and SiC constituents in the composite. The XRD result also proves that the copper coated SiC was free of contaminants. The density of the samples was measured by using a density meter and pycnometer. The result showed that the density of the composite decrease with increasing of volume fraction of SiC reinforcement. For Cu-coated SiC reinforcement, the density was slightly higher compared to non-coated SiC reinforcement. Cu-coated SiC reinforcement gave composites of higher hardness, higher compressive yield strength, lower coefficient of thermal expansion, higher thermal conductivity, lower porosity than the composites with non Cu-coated SiC reinforcement.