Reaction between Cemented Tungsten Carbide and Molten Cu-Mn Alloys

Abstract

Effect of Mn content on the interaction between liquid Cu-Mn alloys containing from 17.7 to 61.1 wt% Mn and WC-8%Co alloys have been studied between 955°C and 1100°C. The diffusion layers formed between both alloys are analysed by means of EPMA, optical microscopy and microhardness measurement.The structures of diffusion layers are tentatively classified into four types depending on the heating temperature and Mn content of the Cu-Mn alloy. Heating near the liquidus temperature of the Cu-Mn binary system yields additional carbide-free layer in the cemented carbide. However at 1100°C, a lower carbide η phase forms in the cemented carbide. The structures of diffusion layers are influenced markedly by cobalt content and WC grain size of the cemented carbide but not significantly by the carbon content. These results are discussed referring to the previous results on the interaction between pure Cu and cemented carbides.