Effects of Mn Content on Mechanical Properties of FeCoCrNiMn_(x)(0≤x≤0.3)High-Entropy Alloys:A First-Principles Study

摘要

Effects of Mn content on mechanical properties of FeCoCrNiMn_(x)(0≤x≤0.3)high-entropy alloys(HEAs)are investigated via first-prmciples calculations combining EMTO-CPA method.Related physical parameters,including lattice constant.elastic constants,elastic modulus,Pugh’s ratio,anisotropy factors,Poisson’s ratio,Cauchy pressure,Vickers hardness,yield strength,and energy factor,are calculated as a function of Mn content.The results show that the resistances to bulk,elastic,and shear deformation decrease with increasing Mn content.Pugh’s ratio B/G indicates that the ductility of FeCoCrNiMn_(x) HEAs has a remarkable reduction between 22 and 24% of Mn content.Meanwhile,Cauchy pressure suggests that the atomic bonding transforms from metallic to directional characteristic from 22 to 24% of Mn content.Vickers hardness and yield strength of FeCoCrNiMn HEA are intrinsically larger than those of FeCoCrNi HEA.Dislocation nucleation easily occurs in FeCoCrNiMn HE A compared to FeCoCrNi HEA,and large dislocation width in FeCoCrNiMnO_(2) HE A results in low stacking-fault energy,which easily induces twinning deformation.This work provides a valuable msieht for further theoretical and experimental study on the mechanical properties of FeCoCrNiMn_(x)(0≤x≤0.3)HEAs.