A two-dimensional computational methodology for high-speed dislocations in high strain-rate deformation

In this paper, shear deformation at high strain rates is modeled within the framework of discrete dislocation plasticity. The total stress and deformation state is split into the state due to the dislocations in an infinite medium and the complementary image field, which is enforced by a finite element solution. The stress and displacement fields for highspeed dislocations are used, as well as a velocity-dependent drag coefficient. Sources and obstacles are put into the material, and constitutive rules are implemented for the creation and annihilation of dislocations. A novel criterion is introduced according to which the properties are projected into the two-dimensional (2D) domain of simulation. The question is addressed whether it is allowed to neglect accelerations, as is done in simulations at lower deformation rates. (C) 2001 Elsevier Science B.V. All rights reserved.