The specific strength of refractory high entropy alloys (RHEAs) is usually impaired due to the high density of constituent elements. In order to develop a low-density RHEA, the microstructure and mechanical property of MoNbVTa0.5-based RHEAs with various Al additions have been investigated in this study. All samples exhibited a monolithic BCC solid solution structure. The addition of Al resulted in improved yield strength but a degraded plasticity at ambient temperature. In contrast, the yield strength consistently decreased with increasing Al content at elevated temperatures, and the softening occurred at ∼1000 °C. MoNbVTa0.5Al0.3 exhibited high specific strengths of 119.2 MPa cm3/g, 108.6 MPa cm3/g and 97.3 MPa cm3/g at 600 °C, 800 °C, and 1000 °C, respectively.

中文翻译：

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MoNbVTa0.5Alx难熔高熵合金的显微组织与力学性能


由于组成元素的高密度，难熔高熵合金 （RHEA） 的比强度通常会受损。为了开发低密度 RHEA，本研究研究了添加各种 Al 的基于 MoNbVTa0.5 的 RHEA 的微观结构和机械性能。所有样品均表现出整体 BCC 固溶体结构。添加 Al 可以提高屈服强度，但在环境温度下的塑性会下降。相比之下，在高温下，屈服强度随着 Al 含量的增加而持续下降，软化发生在 ∼1000 °C 时。 MoNbVTa0.5Al0.3 在 600 °C、800 °C 和 1000 °C 时表现出 119.2 MPa cm3/g、108.6 MPa cm3/g 和 97.3 MPa cm3/g 的高比强度。