Preparation and High Temperature Compression Property of Gradient Structure Copper-Tungsten Based Carbide Composite

CuW80 alloy was prepared by infiltration sintering method, then the gradient structure copper-tungsten based carbide composite was obtained by carburizing process for 4 h at 1 250℃. The compression tests for alloys before and after carburizing were carried out on universal testing machine at different temperatures, and microstructure and compression fracture were observed by scanning electron microscope. Effect of temperature on compression performance for composite was researched, and the failure mechanism was analyzed. The results show that a carburization layer with 70 μm thickness was formed on the surface of composite and surface hardness was improved by 95.1% compared with that of CuW80 alloy. There was a significant work hardening process for composite during room temperature compression process, but the hardening effect gradually weakened as temperature increased. The compressive strength and compression ratio declined as temperature increased. The compression property of composite was better than that of CuW80 alloy. Fracture morphology of composite mainly included dimples and then mostly plastic holes as temperature increased, and compression fracture failure mode was brittle fracture mixed with ductile fracture.