Molecular dynamics simulation of the effects of temperature on the microscopic deformation of single crystal magnesium containing a void and a crack

Abstract Mechanical properties of a material are intensively influenced by the presence of flaws. While temperature is the significant factor of the deformation. An embedded atomic potential function is used to simulate the micro-defect deformation behavior under different temperatures loading in HCP Mg with various defects. Defects consisting of a fixed distribution of void and an edge crack. the results of the simulation were analyzed by the stress-strain curve and atomic trajectory diagram. The results show that the tensile deformation behavior of single crystal magnesium with defects changes obviously with temperature. Increases in temperature lead to decreased peak stress and ascending crack propagation speeds, and toughening the material to fracture ultimately. But the increase of crack-propagating speed is not obvious when the temperature is above 600K. The time that the crack extends to the void and in combination with it at low temperature is delayed as compared to that at high temperature.