Al元素含量对高熵合金AlxFeTiCrZnCu力学性能的影响

First-principle studies of AlxFeTiCrZnCu high entropy alloys with different mole fractions of Al

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)的方法建立高熵合金的固溶结构模型,计算了高熵合金AlxFeTiCrZnCu的结构性能、弹性性能和生成热.计算结果表明,AlxFeTiCrZnCu高熵合金的密度随着Al元素含量的增加而减小,晶格常数在Al元素摩尔含量为1时最小.Al元素含量的增加能提高高熵合金AlxFeTiCrZnCu的力学稳定性.基态总能量和生成热都随着Al元素含量的增加而增加,但是合金系的稳定性和热力学稳定性有所下降.

The structural properties,elastic properties,and the heats of formation for the high entropy alloys(HEAs)AlxFeTiCrZnCu were studied by density functional theory and plane-wave pseudopotential 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 AlxFeTiCrZnCu decreases with the increasing mole fraction of Al,and the lattice parameter is the smallest when the mole fraction of Al is 1.The mechanical stability of HEA AlxFeTiCrZnCu will be improved with the increasing mole fraction of Al.The total energy and the heat of formation increase with the increasing mole fraction of Al,but the system stability and thermodynamic stability decrease.