A comprehensive review on synergy effect between corrosion and wear of cemented tungsten carbide tool bits: A mechanistic approach

Abstract

Cemented tungsten carbide tool bits are widely used in cutting, oil and gas, tunneling, and mining industries there these materials exposed to extremely harsh environments that cause early stages of failure. Tungsten carbide hardmetals are suffering from tribocorrosion, which is a material degradation process that occurs due to the combined action of wear and corrosion. On the one hand, tungsten carbide materials composed of hard ceramics (WC grains) phase in a soft metal matrix binder (Co, Fe, and Ni) phase; hence, it leads to different tribological mechanisms. On the other hand, the different electrode potential of hard WC grains (act as a cathode) and soft binder phase (act as an anode) leads to the formation of the micro galvanic couples between these phases in many aqueous environments causing corrosion. Since tribocorrosion mechanisms are significantly influenced by the varying composition and microstructure of tungsten carbide hardmetals, the effect of size and morphology of the WC grains on tribocorrosion has also been reviewed. This review particularly highlighting the various tribological and electrochemical aspects and their possible degradation mechanisms that are generally encountered by the drill bits during operating conditions. Hence, the understanding of these mechanisms is, therefore, very essential for the selection, improvement, and development of high-performance hardmetals.