Based upon a model of the melting of grain boundaries, the possibility of the existence of a superheated grain boundary state was considered. Molecular dynamics simulations showed that the superheated grain boundary state could be realized in high-symmetry tilt grain boundaries. The sizes of liquid nuclei which exceeded a critical size determined whether or not the superheating grain boundary melted. The results also indicated that an increase in the melting point due to pressure was smaller than the superheating due to a nucleation mechanism.

Superheated Melting of Grain Boundaries. W.Fan, X.G.Gong: Physical Review B, 2005, 72[6], 064121 (5pp)