MOLECULAR DYNAMICS STUDY OF THE INFLUENCE OF LIQUID METAL ABSORPTION ON DISLOCATION EMISSION
液体金属吸附促进位错发射的分子动力学研究

The pair potential of Al-Ga and Cu-Ga have been calculated by Chen's reverse method with the parameters in Rose's equation and the first principle theory. The effect on dislocation emission from crack tip is studied when liquid metal Ga is adsorbed on the crack plane of metal Al or Cu. The results show that for Al the critical stress intensity for dislocation emission would decrease from K_(Ie)=0.5 MPam1/2 to K_(Ie)(L)=0.4 MPam~(1/2) due to the adsorption of Ga, and for Cu from K_(Ie)=0.55MPam_(1/2) to K_(Ie)(L)=0.45MPam~(1/2). It means that the adsorption of liquid metal would facilitate the dislocation emission. On the other hand, vacancy cluster and Frank dislocation would form easily ahead of the crack tip due to the adsorption of liquid Ga.