Effect of Ti content on the microstructure and mechanical properties of TixZrNbMoV lightweight refractory high-entropy alloys

Abstract

In this study, we prepared TixZrNbMoV (x = 1, 1.5, and 2) refractory high-entropy alloys (RHEAs) with varying amounts of Ti by vacuum arc melting. The microstructures of RHEAs are investigated by neutron diffraction, electron backscatter diffraction and transmission electron microscope. The results showed that the TixZrNbMoV alloys mainly comprise body centered cubic phases and hexagonal close packed phases and the average grain size of alloys decreases as the Ti element content increases. Room-temperature compressive tests showed that increasing the Ti content of the alloys improved their ductility, although their strength decreased. Compared with some previously reported RHEAs, the TixZrNbMoV RHEAs prepared in this study possessed better comprehensive mechanical properties, with the specific yield strength of the TiZrNbMoV alloy being as high as 312 kPa·m3/kg. Finally, the deformation behavior of TixZrNbMoV RHEAs was studied by nanoindentation.