Effects of C Element on Microstructure and Mechanical Behavior of AlCrFeMnNi High-entropy Alloy

Abstract

The AlCrFeMnNiC x (x values in molar ratio, x = 0, 0.08, 0.17 and 0.25) were designed and prepared by adding nonmetallic carbon element into the high entropy alloy under near-rapid solidification conditions. The effects of carbon content and heat treatment on microstructure and mechanical properties of AlCrFeMnNiCx alloy were investigated. Experimental results show that the addition of carbon element can lead to the formation of carbonization besides BCC solid solution. There are also amounts of nanoscale particles and laminated structure formed in the samples. Microstructure of near-rapidly solidified AlCrFeMnNiCx alloy turns coarse after aging at 600 ℃ hold for 3 hours. Addition of carbon decreases yield strength of AlCrFeMnNi alloy, but the compressive fracture strength and plastic strain are improved, especially for the samples at aged state having significantly increased mechanical properties. AlCrFeMnNiC 0.08 alloy both in as cast and aged state shows the best compressive fracture strength and plastic strain in the four samples. This experimental study suggests that introduction C elements into the high-entropy alloy can be a developing direction to enhance the properties of high-entropy alloys.

Microstructural evolution and mechanical properties of AlCrFeNiCoC high entropy alloy produced via spark plasma sintering

“…Nevertheless, due to the lack of information the influence of carbon on high entropy alloys is not clarified. Li et al [12] have investigated the microstructure and mechanical behaviour of AlCrFeMnNi high-entropy alloy, finding that as-cast AlCrFeMnNi alloys can lead to the formation of carburisation besides BCC solid solution depending on the carbon content. In another work, the effect of C content on the microstructure and tensile properties of as-cast CoCrFeMnNi high entropy alloy was studied [13].…”