Abstract: Molecular dynamics simulations are employed here to study the behaviors of bulk Ag superheating and melting at high heating rate. The superheating and melting behaviors are found to be strongly affected by the heating rate. The larger the heating rate, the higher the melting temperature, and there is an upper limit for the heating rate induced superheating. Stability study shows that the radomization induced by high heating rate is the main reason for the reduction of the energy barrier on phase transformation and for the existence of dynamic limit of superheating. Both Ag crystals and Ag crystals with defects are studied. The upper limit of heating rate induced superheating of perfect Ag crystal is determined to be around 1 450 K.

Key words: Molecular dynamics simulations, Melting, Superheating, Metal Ag