Investigation of mechanical and corrosion properties of light and high hardness cast AlTiVCrCu0.4 high entropy alloy

The unique structural composition of Dual-phase high entropy alloys (HEAs) requires further investigation of the influence of different structures on the mechanical properties and corrosion behavior of such alloys. In this work, a low density (5.25 g/cm3) and high hardness (871 HV) AlTiVCrCu0.4 HEA consisting of a biphasic structure (BCC + HCP) was designed and its phase distribution, phase composition and phase structure were determined. Compression tests show that the alloy has a yield strength of 949.16 MPa, a compressive strength of 1005.16 MPa, and a fracture strain of 5.53%. The nanoindentation test shows that the BCC phase has excellent creep properties. And it was found that HCP phase was helpful to improve the hardness of the HEA. The AlTiVCrCu0.4 HEA showed excellent corrosion performance in 0.6 M NaCl solution with a corrosion current density of only 1.37 x 10-7A/cm2. The protective film of the BCC phase is composed of metal oxides and unoxidized metal atoms, and this composition has excellent corrosion resistance.