Effects of V Addition on Microstructural Evolution and Mechanical Properties of AlCrFe2Ni2 High-Entropy Alloys

Abstract

The effects of vanadium addition on the microstructural evolution and mechanical properties of AlCrFe 2 Ni 2 high-entropy alloy (HEA) were investigated. The results showed that the AlCrFe 2 Ni 2 V 0.2 HEA was composed of FCC phase, disordered BCC phase, and ordered BCC (B2) phase. With the increase in vanadium content, the formation of FCC phase was inhibited, and a transition from FCC phase to BCC phase occurred. The FCC phase disappeared completely when the value of x exceeds 0.4 in AlCrFe 2 Ni 2 V x HEAs. Besides, the amplitude-modulated microstructure morphology transformed from a B2 phase matrix with dispersed BCC nano-phase into an alternating interconnected B2 and BCC phases. Vanadium element has the function of stabilizing BCC phase and B2 phase in AlCrFe 2 Ni 2 V x alloys. The hardness of AlCrFe 2 Ni 2 V x alloys increased from HV 332.4 to HV 590.7, while the yield strength increased from 765 to 1744.6 MPa with increasing vanadium content, which was mainly due to the decreasing content of FCC phase and the solid solution strengthening of vanadium element. At the same time, the compression ratio of the alloys decreased with the disappearance of the FCC phase. Among the alloys, the AlCrFe 2 Ni 2 V 0.2 alloy possessed the most excellent comprehensive mechanical properties with yield strength, fracture strength, and compressive ratio 1231.1, 2861.9 MPa, and 44.5%, respectively.

Mechanical and Tribological Performance of AlCrFeCuNi-(Vx) HEAs Synthesized via Arc Melting technique

“…Chen et.al, [20] discovered that increasing the V content boosted the hardness and wear resistance properties of the Al0.5CoCrCuFeNi HEA. In AlCrFe2Ni2Vx HEAs, Duan et.al, [21] found that an increase in V content prevented the development of the FCC phase and caused a change from the FCC phase to the BCC phase. The yield strength of AlCrFe2Ni2Vx alloys rose with increasing V content, which was mostly caused by the lowering concentration of FCC phase and the strengthening of V element in solid solution.…”