FeCrNiCoCu纳米压痕性能的分子动力学研究

Molecular dynamics simulation of nanoindentation properties of FeCrNiCoCu

纳米压痕是研究金属特性最广泛的方法之一.因此,本文采用分子动力学方法研究了晶粒数、压痕半径和压痕速度对FeCrNiCoCu压痕性能的影响.结果表明,晶粒数从4增加到16,杨氏模量和硬度值逐渐减小,呈现反Hall-Petch现象;随着压头半径的增加,杨氏模量增大,硬度受接触面积的影响较大而减小,较大的压头半径有利于模型内部位错的产生和扩展;压入速度对杨氏模量和硬度的影响微弱,压入速度越快,位错密度越低,位错传播速度越慢.本工作以期为FeCrNiCoCu的研究提供理论指导.

Nanoindentation is one of the most widely used methods to investigate the characteristics of metallic materials.Thus,in this work,molecular dynamics simulation is employed to investigate the effects of the number of grains,the indenter radius and the indenter velocity on the indentation performance of the FeCrNiCoCu.The results show that when the number of grains increases from 4 to 16,the Young's modulus and hardness gradually decrease,showing an inverse Hall-Petch phenomenon.With the increase of the indenter radius,the Young's modulus increases,the hardness is greatly affected by the contact area,and the larger indenter radius is conducive to the generation and expansion of dislocation in the model.The effect of pressing speed on Young’s modulus the hardness is weak.The higher the pressing speed,the lower the dislocation density and the slower the dislocation propagation.The purpose of this paper is to provide theoretical guidance for the study of FeCrNiCoCu.