Microstructure and mechanical properties of TiZrVMnCu high entropy alloy by addition of Er element

Abstract

To improve the ductility and toughness of refractory high entropy alloys (HEAs), TiZrVMnCu-xEr HEAs were designed and fabricated via spark plasma sintering. With the addition of Er, the relative density, microhardness, and compressive strength of the HEAs increased. TiZrVMnCu-0.5 %Er HEA has the highest compressive strength (1520.5 MPa) and good deformation ability (strain 14.7 %). The good mechanical properties are mainly contributed to the effective combination of the hard TiZrVMn and soft CuZr phases. Appropriate Er content can: (i) reduce the content of ZrO2 and improve the relative densities; (ii) diffuse into matrix to achieve solid solution strengthening; (iii) refine the grains. Excess Er2O3 particles deteriorated the mechanical properties.