第一性原理计算Cu元素含量对高熵合金AlCoCrCu_xFeNi的影响

采用第一性原理密度泛函理论,结合平面波赝势和广义梯度近似(GGA),用虚拟晶体近似(VCA)的方法建立晶体结构模型,计算了高熵合金AlCoCrCuxFeNi的结构性能、弹性性能和生成热。计算结果表明,高熵合金的密度随Cu元素摩尔含量的增大而增大,晶格常数在Cu元素摩尔含量为1.5时最小。Cu元素的摩尔含量并不能改变高熵合金AlCoCrCuxFeNi的力学稳定性。生成热随着Cu元素摩尔含量的增大而减小,但皆为负值。表明高熵合金AlCoCrCuxFeNi在热力学条件下是稳定的。

First-principle studies of AlCoCrCuFexNi high entropy alloys with the different mole fractions of Cu

The structural properties, elastic properties, and the heat of formations for the high entropy alloys (HEAs) AlCoCrCuxFeNi were studied by density functional theory and plane-wave pseudopotental technique with generalized gradient approximation (GGA), the crystal structure was built with the Virtual Crystal Approximation (VCA). The calculated results indicate that the mass density of HEA AlCoCrCuxFeNi increases with the increasing mole fraction of Cu, the lattice parameter is the largest when the mole fraction of Cu is 1.5. The mechanical stability of the HEA AlCoCrCuxFeNi is nothing to do with the mole fraction of Cu. The heat of formation decreases with the increasing mole fraction of Cu, but the HEAs AlCoCrCuxFeNi are thermodynamically stable due to their negative heats of formation.