The effects of grain size and temperature on mechanical properties of CoCrNi medium-entropy alloy

The mechanical properties and deformation mechanisms of CoCrNi medium-entropy alloy are studied through molecular dynamics simulations. The effects of temperature and average grain size on the elastic modulus, Poisson's ratio, yield stress, and maximum flow stress are investigated.The constant pressure molecular dynamics method is used to calculate the elastic modulus and Poisson's ratio of the alloy at different temperatures and average grain sizes. Simple tension simulations are conducted to determine the yield stress and maximum flow stress as a function of average grain size. The study also analyzes the dislocation behavior near grain boundaries at different temperatures using molecular dynamics simulations. The Hall-Petch and inverse Hall-Petch relationships are employed to describe the grain size-dependent deformation behavior of the alloy.