Synergetic Enhancements on the Mechanical and Tribological Performance of Al10Cr17Fe20NiV4 Medium‐Entropy Alloys Induced by Nano‐Al2O3 Particles

Due to the lack of mature mechanisms to support the wear performance of medium‐entropy alloys (MEAs) with nonequiatomic ratios, the practical application of medium alloy in wear‐resistant structural materials is severely restricted. Herein, a nonequiatomic Al10Cr17Fe20NiV4 medium entropy reinforced by nano‐Al2O3 particles is designed and fabricated through high‐energy ball milling and hot pressing. During the high‐energy ball‐milling process, a supersaturated solid solution with a single face‐centered cubic structure is formed in the Al10Cr17Fe20NiV4. The hardness of Al10Cr17Fe20NiV4‐reinforced Al2O3 nanoparticles is 13.9 ± 0.4 GPa measured using nanoindentation, which is about twice high as that of MEAs. Both Al10Cr17Fe20NiV4 and Al10Cr17Fe20NiV4–Al2O3 are implemented to ball‐on disc sliding wear at ambient temperature against an alumina ball and Si3N4 ball. The wear test indicates that the wear rate of Al10Cr17Fe20NiV4‐Al2O3 against Al2O3 and Si3N4 is 13.87 × 10−5 and 9.47 × 10−5 mm3 N−1 m−1, which is lower than those of the Al10Cr17Fe20NiV4, respectively. The significant enhancements in the mechanical and wear performance can be mainly due to the coupled effects of grain refinement and particle dispersion strengthening induced by nano‐Al2O3 particles. The enhanced mechanical and wear properties of Al10Cr17Fe20NiV4 make it a competitive candidate to be applied in advanced mechanical manufacturing. Al10Cr17Fe20NiV4 and Al10Cr17Fe20NiV4–Al2O3 are fabricated by high‐energy ball milling and hot pressing. Dry sliding wear behavior of Al10Cr17Fe20NiV4 and Al10Cr17Fe20NiV4–Al2O3 against alumina ball and silicon nitride ball show that Al10Cr17Fe20NiV4 and Al10Cr17Fe20NiV4–Al2O3 exhibit low wear rates at different conditions. The wear performance of Al10Cr17Fe20NiV4–Al2O3 is substantially enhanced than Al10Cr17Fe20NiV4, which should be attributed to the strengthening effect of grain refinement.