The Transient Motion of a Ramp-Core Supersonic Dislocation

Abstract

The transient motion of a ramp-core dislocation spreading from −∞<x<∞ and jumping from rest to a supersonic speed in the x direction, is investigated by analysis on the complex transform plane. The new result of this analysis is that, instead of the Mach cone of the Volterra dislocation, there are two lines of discontinuity (of the stress) propagating in the ±z directions, inside of which there are arctan delta sequence (ε≠0) radiated supersonic fields, as well as subsonic fields. The lines of discontinuity arise at the tangent point of the Mach wavefront (ε=0) to the cylinder with radius r=c2t.