Irradiation of metals with high-energy atomic particles creates obstacles to glide, such as voids, dislocation loops, stacking-fault tetrahedra and irradiation-induced precipitates through which dislocations have to move during plastic flow. Approximations based on the elasticity theory of defects offer the simplest treatment of strengthening, but were deficient in many respects. It was now widely recognised that a multiscale modelling approach should be used, wherein the mechanisms and strength parameters of interaction were derived by simulation of the atomic level to feed higher-level treatments based on continuum mechanics. Atomic-scale simulation was developed to provide quantitative information on the influence of stress, strain rate and temperature. Recent results of modelling dislocations gliding under stress against obstacles in a variety of metals across a range of temperature were considered. The effects observed include cutting, absorbing and dragging obstacles. Simulations of 0K provide for direct comparison with results from continuum mechanics, and although some processes could be represented within the continuum treatment of dislocations, others cannot.

Modelling Dislocation–Obstacle Interactions in Metals Exposed to an Irradiation Environment. D.J.Bacon, Y.N.Osetsky: Materials Science and Engineering A, 2005, 400-401, 353-61