Effect of Alloying Components on the Tribocorrosion Properties of Tungsten-Carbide Cermets

We study the corrosion and tribocorrosion properties of tungsten-carbide metal composites alloyed with graphite and chromium and vanadium carbides in a 3% NaCl solution. It is shown that the addition of 2–4% of graphite to the VN20 composite intensifies local corrosion processes because graphite inclusions serve as additional cathodic sections. This deteriorates the tribocorrosion behavior of the alloys, including the alloys alloyed with chromium and vanadium carbides because the corrosion processes in the contact zone lead to the crumbling of carbide inclusions playing the role of abrasive. We revealed the high wear resistance of the (VN20 + 1% VC)–(VN20 + 1% Cr3C2 ) friction couple in a 3% NaCl solution. After friction, the corrosion current density decreases on both contacting surfaces by almost an order of magnitude, which corresponds to the formation of secondary structures guaranteeing corrosion protection.