High-velocity dislocations: Effective mass, effective line tension and multiplication

Abstract

Abstract An expression is derived for the effective mass of an edge dislocation moving with uniform velocity v in an isotropic elastic medium. Ishioka's analysis of the effective line tension of stationary dislocations is extended to the uniformly moving dislocations. The effective line tension of the moving edge dislocation becomes negative for c ≥ v ≳ 0·81c, where c is the velocity of transverse sound waves, when Poisson's ratio v = 0·3. The limiting velocity v c of the edge dislocation is not c but about 0·81c. Because the edge dislocation becomes unstable for c ≥ v ≥ v c, multiplication of the dislocation is expected at v c.