Microstructures and mechanical properties of multiprincipal component CoCrFeNiTix alloys

The purpose of this study is to investigate the effects of Ti addition on the microstructures and mechanical properties of multiprincipal component CoCrFeNiTix (x values in molar ratio, x=0, 0.3, and 0.5) alloys. The CoCrFeNi quaternary alloy displayed a crystalline structure constructed by a simple face-centered cubic solid solution, whereas a plate-like structure consisting of a mixture of (Ni, Ti)-rich R phase and (Cr, Fe)-rich σ phase was observed within the face-centered cubic matrix of a CoCrFeNiTi0.3 alloy. In a CoCrFeNiTi0.5 alloy, an face-centered cubic matrix, a (Ti, Co)-rich Laves phase, and R+σ mixed phases were discovered. The compressive strength of the alloys rose by approximately 75% after the addition of Ti. Alloys with high levels of Ti content had high yield stress values and low ductility values. The solid-solution strengthening of the face-centered cubic matrix and the secondary-phase hardening were the two main factors that strengthened the alloy. The CoCrFeNiTi0.3 alloy exhibited a compressive strength of 1529 MPa and a fracture strain of 0.60; this indicates that this material shows potential for the development of a ductile, high-strength alloy.