Time Dependent Rate Theory for Diffusional Defect Processes

摘要

Effective Medium Theory is used to derive the equation governing the time evolution of the volume averaged defect concentration in a system containing cavities and dislocations. Any generation of defects due to external causes is assumed to be spatially homogeneous but may vary with time in an arbitrary manner. Within the approximation of spatial uniformity the theory is suitable for application to the study of irradiation effects in fusion reactor components. Specific examples of the general formalism are analyzed in detail. These indicate that although differences do exist between the present theory and that which would be inferred from a simple extension of steady state considerations, such departures are of minor practical significance. The formalism also permits a more detailed justification of steady-state growth models to be given than has heretofore been available. The main emphasis for irradiated materials is placed upon the domain where intrinsic recombination between interstitials and vacancies is a minor source of defect loss. However, a brief discussion of this process is appended in order to cast it within the present formalism. (ERA citation 10:013580)