SUPER HARD ALLOY MEMBER HAVING HARD SURFACEECOATING LAYER WITH HIGH ADHESIVE STRENGTH

摘要

PURPOSE:To form hard surface-coating layer excellent in adhesive strength, wear resistance, by coating the surface of a super hard alloy member with three layers consisting of an inner layer of carbide, nitride, and carbonitride of titanium, an intermediate layer of titanium carbonate, and an outer layer of Al2O3 by chemical vapor deposition. CONSTITUTION:Super hard alloy member is made by sintering hard substance such as carbides, nitrides, or carbonitrides of 4a, 5a, 6a group metals of the periodic table using Fe, Ni, Co, W, Mo, Cr etc. as bonding material. A layer 0.5-20mum in thickness comprising one or more members selected from the group consisting of TiC, TiN, or TiCN is formed on the surface of the alloy member by chemical vapor deposition. Then an Ti carbonate layer 0.5-10mum in thickness shown by a composition formula TiCxOy, where x is 0.9-0.4, y is 0.1-0.6, is formed as an intermediate layer by chemical vapor deposition. Finally a layer of Al2O3 0.5-10mum in thickness is formed as an outer layer on the intermediate layer. Hereby hard coating layers having high adhesive strength and excellent wear resistance are formed on the super hard alloy member.