Study of Electrical Resistivity of Powder Materials Obtained by Oxidation of Hard Alloys

An electrical resistivity of oxide powder materials obtained by high-temperature heating of hard-alloy tool materials has been measured. The resistivity of oxide powder increases with increasing cobalt content in raw hard alloys as well as the oxidation temperature. On the contrary, the increase of concentration of titanium and tantalum carbides is accompanied by the resistivity reduction. The increase of pressure on the powder also results in the resistivity decrease. There exists a correlation between the wear resistance of cutting tools and pressure dependence of the resistivity of oxide powders. Therefore the measurement of the resistivity of oxide powders can be successfully applied for the quality estimation and forecasting of the service properties of hard-alloy production.