AlxFeCoNiB0.1高熵合金的微观组织和力学性能研究

Microstructure and mechanical properties of AlxFeCoNiB0.1 high entropy alloy

摘要:

采用真空电弧炉熔炼制备了AlxFeCoNiB0.1（x=0.4,0.5,0.8,1.2,1.6 at%）高熵合金，并对其微观组织和力学性能进行测试。随Al含量增加，合金的铸态枝晶由FCC相转变为B2(AlNi)/BCC相。当x=0.4和0.5时，合金的组织由枝晶FCC相和枝晶间组织B2相及(Fe,Co)2B组成；x=0.8时，枝晶由B2相组成，枝晶间由FCC相及(Fe,Co)2B组成；x=1.2时，枝晶间由共晶组织FCC+(Fe,Co)2B组成，BCC呈纳米级颗粒状；x=1.6时，共晶组织消失。随Al含量的增加，抗压拉强度先上升后下降，Al含量为0.8时达到峰值，为2243MPa，适量的Al能提高高熵合金综合力学性能。

Abstract:

AlxFeCoNiB0.1 (x=0.4, 0.5, 0.8, 1.2, 1.6where, x is the mole percentage) were prepared by vacuum arc melting.The microstructure and mechanical property of AlxFeCoNiB0.1 high-entropy alloys were investigated. With the increase of Al content, the cast dendrites of the alloy were changed from FCC phase to B2 (AlNi) /BCC phase. When x= 0.4 and 0.5, the microstructures of the alloy were consisted of the dendrite FCC phase and the interdendritic B2 phase and (Fe, Co) 2B; when x=0.8, the dendrites were composed of B2 phase, and the interdendrites were composed of FCC phase and (Fe, Co) 2B; when x=1.2, the interdendritic structures were consisted of the eutectic FCC+ (Fe, Co) 2B, and the nanoscale granulars are the BCC phase;When x=1.6, the eutectic structures disappeared. With the increase of Al content, the compressive strength increased first and then decreased. When the content of Al was 0.8, it reached the peak value of 2243MPa. Appropriated amount of Al can improve the comprehensive mechanical properties of high entropy alloy。