Effect of Ti Addition on the Microstructure and Property of FeAlCuCrNiMo0.6 High-Entropy Alloy

FeAlCuCrNiMo0.6Tix (x = 0.2, 0.6, 0.8) high-entropy alloys were fabricated with flux-cored wire and surfaced on low-carbon steel by gas metal arc welding. The effect of Ti addition on the microstructures and properties of FeAlCuCrNiMo0.6Tix HEAs surfacing layer was systematically studied. The results show that FeAlCuCrNiMo0.6Tix HEAs surfacing layer exhibits a majority of BCC solid solution based on Fe-Cr phase and a small amount of MC phase. Microhardness and wear tests results show that the addition of Ti can significantly improve the microhardness and wear resistance of the surfacing layer. The microhardness of surfacing layer can reach up to 642 HV0.5, which is about 2.8 times that of the substrate. Meanwhile, the wear mass loss is minimum. Electrochemical corrosion test results show that the addition of Ti can improve the corrosion resistance of surfacing layer, which is better than 304 stainless steel substrate. With the increase in Ti, the corrosion resistance increases first and then decreases. When the Ti content is 0.6, the self-corrosion current density of polarization curve is the smallest, the capacitive impedance radius of electrochemical impedance spectroscopy is the largest, and the corrosion resistance effect is the best.