Numerical Simulation of Temperature Dependence of Tensile Mechanical Properties for Single Graphene Sheet

The tensile mechanical properties of the armchair and zigzag single graphene sheets at different temperatures(0~3 000 K) were investigated based on molecular dynamics simulation with Tersoff bond-order interatomic potential.The dependence of the tensile mechanical properties of the sheets on the temperature was predicted and analyzed.A study was also made of the difference of the tensile mechanical properties between armchair and zigzag sheets at different temperatures.Simulation results indicate that the tensile mechanical properties and deformation mechanism of the sheets are strongly dependent on the temperature.The Young's modulus,tensile strength and limit tensile strain of the two chiral sheets all decrease significantly with the increasing temperature.It is also found that the mechanical anisotropy of the sheets is also affected by the temperature.When the temperature is less than 600K,the mechanical properties of armchair sheets are superior to those of the zigzag ones.However,when the temperature is over 600 K,this superiority diminishes gradually and even turns into inferiority,especially at a high temperature.