Molecular dynamics simulation of strain effects on surface melting for metal Cu
应变效应对金属Cu表面熔化影响的分子动力学模拟

Molecular dynamics simulations of surface melting process at different strain values were performed for metal Cu(110). The variation of the structure and energy in the system and the movement of the interface position between solid and liquid during surface melting were observed. The interaction between atoms in the system adopts the embedded atom potential proposed by Mishin. Cu(110) surface pr emelts below thermal melting point and the thickness of quasi-liquid film grows with temperature increasing. Beyond the thermal melting point, the velocity of t he interface between solid and liquid is linearly proportional to temperature, t he melting point is extrapolated to be 1380K which accords with the experimental data of 1358K. Strain lowers the melting point and accelerates the premelting p rocess. The thickness of quasi-liquid grows with increasing strain at the same t emperature. The increase of solid free energy induced by strain is the main fact or that decreases surface thermal stability, the direction of strain relative to the surface stress also effects the premelting process.