Effect of core impurity on kink soliton motion in dislocation line

Modified Sine-Gordon equation is established to investigate the kink soliton motion affected by core impurities. The dragging force that the core impurities exert on the moving kink soliton is determined by computer simulation of diffusing of solute atoms in dislocation core. The soliton motion can be dissolves into two kinds of movement : the changing of soliton position and soliton shape. These two kinds of movements correspond to the longitude core diffusion(LCD) and transverse core diffusion(TCD) of solute atoms respectively. We solve the equation of these motions numerically, temperature internal friction peak and stress amplitude internal friction peak are discussed. The results are compared with the anomalous internal friction peaks in Al-Mg,Al-Cu alloy.