Corrosion Inhibition on Cemented Tungsten Carbides

Abstract

Cemented tungsten carbide (WC-Co) materials are made of tungsten-carbide grains embedded in a cobalt matrix and are used for making metal cutting and mining tools through powder metallurgical processes. Cobalt is known to be prone to corrosion in aqueous environments. Various surface preparation processes for cemented carbide exposes the cobalt phase in multiple aqueous environments where the corrosion mechanism is not well understood. Therefore, this study aims to understand the corrosion behavior of cemented carbides with different inhibitors in varying pH and temperature environments. The study also evaluates conditions where the corrosion inhibitor can be removed or reduced for different surface conditions for cemented carbide processes, and for alternate corrosion inhibitors with lesser health and environmental impacts. The results of this study will help improve cemented carbide tool performance in highly demanding service conditions and applications in oil and gas extraction in tetra-phasic conditions (seawater, sand, liquid, and gaseous hydrocarbons).