【摘要】 采用特殊准随机结构建模与第一性原理计算分析了间隙原子C、O掺杂对等物质的量比MgAlLiSbAg轻质高熵合金相稳定性和力学性能的影响。结果表明，MgAlLiSbAg倾向于形成单相BCC固溶体结构，较高浓度(4.76%,原子分数)的O原子掺杂能保持相结构稳定，而较高浓度的C原子或较低浓度(2.44%)的O原子掺杂则诱导了合金从BCC相结构到FCC相结构的转变。C或较低浓度O的掺杂会降低MgAlLiSbAg合金的强度、塑性，而BCC结构中掺杂较高浓度的O能够实现合金强塑性的协同提升。更多还原

【Abstract】 The effects of C and O interstitial atoms on the phase stability and mechanical properties of the equimolar ratio MgAlLiSbAg lightweight high-entropy alloy were investigated using special quasi-random structure modeling and first-principles calculations. The results show that MgAlLiSbAg tends to form stable BCC solid solution structure. Doping of O atoms at a higher concentration(4.76%, atomic fraction) helps to maintain the BCC structure stability, while doping of C atoms at a higher concentration or O atoms at a lower concentration(2.44%) will induce phase transformation from BCC structure to FCC structure. Doping with C or lower concentrations of O decrease the strength and ductility of the MgAlLiSbAg HEA, while the strength and plasticity of the alloy can be synergistically improved by doping higher concentrations of O atoms in BCC structure.更多还原