Anisotropic nucleation and growth of multi-classes of dislocation loops under the combined actions of fast-neutrons and an external applied stress were considered in modelling dislocation structure development in metals and alloys. The stochastic nature of the nucleation kinetics was formulated via the Fokker–Planck equation. The strain derived from the climb of the anisotropic dislocation structure was separable into volumetric and deviatoric components, corresponding respectively to swelling and creep. The creep contribution resulting from the development of the stress-induced dislocation anisotropy was found to be very significant and exhibits a strong correlation with swelling. For stainless steel, the model explained very well the complex deformation behavior observed in a wide variety of in-reactor experiments.

Modeling Dislocation Structure Development and Creep–Swelling Coupling in Neutron Irradiated Stainless Steel. A.A.Semenov, C.H.Woo: Journal of Nuclear Materials, 2009, 393[3], 409-17