Computational modelling of single crystals
The physical basis of computationally tractable models of crystalline plasticity is reviewed. A statistical mechanical model of dislocation motion through forest dislocations is formulated. Following Franciosi and co-workers (1980-88) the strength of the short-range obstacles introduced by the forest dislocations is allowed to depend on the mode of interaction. The kinetic equations governing dislocation motion are solved in closed form for monotonic loading, with transients in the density of forest dislocations accounted for. This solution, coupled with suitable equations of evolution for the dislocation densities, provides a complete description of the hardening of crystals under monotonic loading. Detailed comparisons with experiment demonstrate the predictive capabilities of the theory. An adaptive finite element formulation for the analysis of ductile single crystals is also developed. Calculations of the near-tip fields in Cu single crystals illustrate the versatility of the method.
© 1993 IOP Publishing Ltd Received 26 June 1992, accepted for publication 8 October 1992, Print publication: Issue 3 (April 1993) The support of the US Office of Naval Research through grant N00014-90-5-1758 is gratefully acknowledged. MO is grateful for support received while on visit at the LPMTM of the Universite Paris Nord, where some aspects of the work reported in this paper were partly completed. MO is also indebted to P Franciosi for many helpful discussions.
Published - CUImsmse92.pdf