Light and strong AlxCrNbVMo (x = 0, 0.5, and 1.0) refractory high-entropy alloys (RHEAs) were designed and fabricated via a the powder metallurgical process. The microstructure of the AlxCrNbVMo alloys consisted of a single BCC crystalline structure with a sub-micron grain size of 2-3 μm, and small amounts (< 4 vol.%) of fine oxide dispersoids. This homogeneous microstructure, without chemical segregation or micropores was achieved via high-energy ball milling and spark-plasma sintering. The alloys exhibited superior mechanical properties at 25 and 1000℃ compared to those of other RHEAs. Here, CrNbVMo alloy showed a yield strength of 2743 MPa at room temperature. Surprisingly, the yield strength of the CrNbVMo alloy at 1000℃ was 1513 MPa. The specific yield strength of the CrNbVMo alloy was increased by 27% and 87% at 25 and 1000℃, respectively, compared to the AlMo_0.5NbTa_0.5TiZr RHEA, which exhibited so far the highest specific yield strength among the cast RHEAs. The addition of Al to CrNbVMo alloy was advantageous in reducing its reduce density to below 8.0 g/cm³, while the elastic modulus decreased due to the much lower elastic modulus of Al compared to that of the CrNbVMo alloy. Quantitative analysis of the strengthening contributions, showed that the solid solution strengthening, arising from a large misfit effect due to the size and modulus, and the high shear modulus of matrix, was revealed to predominant strengthening mechanism, accounting for over 50% of the yield strength of the AlxCrNbVMo RHEAs.

通过粉末冶金工艺设计和制造了轻质和坚固的AlxCrNbVMo（x = 0、0.5和1.0）难熔高熵合金（RHEA）。AlxCrNbVMo合金的微观结构由单一的BCC晶体结构组成，亚微米晶粒尺寸为2-3μm，并且有少量（<4 vol。％）的细氧化物弥散体。通过高能球磨和火花等离子体烧结可以实现这种均匀的微观结构，而没有化学分离或微孔。与其他RHEA相比，该合金在25和1000℃时具有优越的机械性能。此处，CrNbVMo合金在室温下的屈服强度为2743 MPa。出乎意料的是，CrNbVMo合金在1000℃下的屈服强度为1513 MPa。CrNbVMo合金在25和1000℃时的比屈服强度分别提高了27％和87％，_0.5 NbTa _0.5 TiZr RHEA，迄今为止在铸造的RHEA中表现出最高的比屈服强度。将Al添加到CrNbVMo合金中有利于将其降低密度降低到8.0g / cm ^3以下，同时由于Al的弹性模量比CrNbVMo合金的低得多而使弹性模量降低。对强化作用的定量分析表明，固溶强化是由主要的强化机理所致，该固溶强化是由于尺寸和模量以及基体的高剪切模量导致的大失配效应所致，占屈服强度的50％以上AlxCrNbVMo RHEA的强度。