Effects of NbC addition on mechanical and tribological properties of AlCrFeNi medium-entropy alloy

AlCrFeNi medium-entropy alloy (MEA) without expensive Co has demonstrated superior properties over the well-known AlCoCrFeNi high-entropy alloy. We added NbC particles to the MEA to make NbC-reinforced MEA alloys or MEA-matrix composites, and evaluated their wear resistances and mechanical properties. The materials showed considerably improved performance. To well judge the NbC-MEA for realistic applications, the wear resistance of the NbC-MEA samples was compared with those of a few industrial wear-resistant materials, e.g., high -Cr cast iron (HCCI) and WC-Co composites. It was demonstrated that the MEA samples with 40-60 vol% NbC exhibited markedly higher wear resistance than the reference materials, and the MEA demonstrated high superiority over the widely used Co as the metal-matrix for developing wear-resistant metal-matrix composites (MMCs).