Research on the microstructures and mechanical properties of novel Cu-rich CuxNiTiCr (x = 2, 3, 4, 5) medium-entropy alloys

Abstract

In this manuscript, the CuxNiTiCr (x = 2, 3, 4, 5) series medium-entropy alloys (MEAs) were produced by non-consumable vacuum arc melting furnace and the effects of Cu contents on the microstructures, phases and mechanical properties were studied. The results show that the CuxNiTiCr (x = 2, 3, 4, 5) series MEAs are mainly composed of FCC, BCC1 and BCC2 phases. With the increase of Cu contents, the dendrites are refined and the amount of FCC phase increases. The strength of the alloys decreases with the increase of Cu content, but the ductility of the Cu5NiTiCr is the highest. With the increase of Cu content, the vickers hardness of the alloy decreases, while the hardness value does not change when the x exceeds 4. The Cu2NiTiCr and Cu3NiTiCr MEAs also have good wear resistance.