Enhanced Tribological Properties of Electrodeposited Fe-W Alloy Coatings through Carburization

Carburization is a promising surface-hardening approach to maximize the tribological and mechanical properties of metals and alloys by making thin-layer surface carbides. The current study investigates the effect of carburizing on the electrodeposited Fe-W alloy coating. This process involeves the thermal decomposition of ethanol in an argon (Ar) atmosphere at varying temperatures. The amorphous electrodeposits of Fe-W alloy coating formed at optimized current density (500 A/cm²) are transformed to the uniform W-rich reinforced bimetallic carbide (Fe₃W₃C) layers at a carburizing temperature of 850 °C. The sample Fe-50WC (850 °C) shows enhanced hardness and highest wear resistance with a lowest specific wear rate (10^-7 mm³/Nm) as compared to the as-electrodeposited Fe-W alloy and other Fe-W, Co-W, and hard chromium coatings reported in the literature. The present strategy can be applied to develop alternative, low cost, and environmentally friendly W-based composite coatings to replace the toxic chromium coatings.