Corrosion Science | 2019
Effect of roughness on general corrosion and pitting of (FeCoCrNi)0.89(WC)0.11 high-entropy alloy composite in 3.5 wt.% NaCl solution
Abstract
Abstract The influence of roughness on general corrosion and pitting of (FeCoCrNi)0.89(WC)0.11 high-entropy alloy composite in 3.5\u2009wt.% NaCl solution was studied by electrochemical measurements and composition characterization. The results showed that a dual-layer passive film formed on WC-HEA composite, and its stability and compactness increased with the decreased roughness. The predominant corrosion type of the composite changed from general corrosion to pitting with the decrease of roughness. Galvanic corrosion occurred between the FCC phase (cathode) and Cr-rich carbide (anode) on the smooth composite surface, inducing the pitting initiation and development of the Cr-rich carbide at the two-phase interface.