Microstructure and wear properties of WC–TiC–Co/CuZnNi composite surface coating

Abstract

The microstructure and wear behavior of WC–TiC–Co/CuZnNi composite surface coating has been investigated by means of scanning electron microscope (SEM), electron dispersion X-ray analysis (EDXA) and wear test. The oxidation behavior of WC–8TiC–8Co and WC–8Co hard metal in the temperature range between 600 and 1000 °C was also researched. The oxidation mass gain of WC–8TiC–8Co hard metal is less than the WC–8Co hard metal. The particle of hard metal is surrounded by the α-Cu + β-Zn phase in the surface coating. The size of hard metal is almost unchanged from its original one. There exists an inter-diffusion zone at the interface of the hard metals and Cu-based matrix. The wear volume of both the WC–8TiC–8Co/CuZnNi and WC–8Co/CuZnNi composite surface coatings increased with the increasing of applied load. However, the composite surface coating of WC–8TiC–Co/CuZnNi exhibited lower wear volume than that of WC–8Co/CuZnNi composite surface coating. According to the results of engineering application, the working efficiency and employing life of milling tools, which were surfaced WC–8TiC–8Co/CuZnNi surface coating, is by approximately 2–3 times the milling tools surfaced WC–8Co/CuZnNi surface coating.