高熵合金CoCrFeMnNi尺寸依赖性的纳米压痕模拟OA

A molecular dynamics method is used to simulate the nanoindentation deformation process of CoCrFeMnNi high-entropy alloy.Aiming at the two factors of indenter size and indentation crystal orientation,the way of influencing the mechanical properties of this material and the corresponding microstructure evolution mechanism are investigated.The correctness of the simulation is verified by Hertzian curve fitting,and the results of the study show that as the size of the indenter increases from 3 nm to 6 nm,the material undergoes a plastic delay phenomenon and the hardness decreases with the change,decreasing by 9.78%,4.62%,and 12.97%along the three indentation directions[001],[110]and[111],respectively;both the dislocation length and the dislocation density show an overall increasing trend with increasing indenter size;but when the size of the indenter increases to a certain extent,the dislocation loop detachment phenomenon occurs during the indentation process along the grain direction[110],[111],resulting in no growth of dislocation density under individual working conditions.Overall,as the size of the indenter increases,there is an increase in the number of open slip systems in the CoCrFeMnNi high-entropy alloy material and an increase in plastic deformation.