A critical review of the tribocorrosion of cemented and thermal sprayed tungsten carbide

Cemented and thermal sprayed tungsten carbide are extensively used in a wide range of applications, ranging from downhole drilling tools and oil and gas valves to gas turbine engines. These WC based systems offer improved wear resistance as a result of hard ceramic phases surrounded by a metallic binder matrix. However, the presence of hard and soft phases within these materials also leads to differing wear mechanisms and the formation of micro-galvanic couplings in aqueous environments often result in a reduction in combined wear-corrosion resistance. This paper examines the wear-corrosion performance of these WC based systems in a range of wear, electrochemical and wear-corrosion tests to develop models and establish relationships between wear mechanisms and environmental factors such as pH.