DIFFUSION CREEP UNDER NEUTRON IRRADIATION

Integration of the diffusion equation shows that in a uniform stress or a non divergent stress gradient, the instantaneous neutron flux has no effect on steady diffusion controlled creep. This statement is general; it allows the mutual recombination of vacancies and interstitials, the creation of dislocation loops and other sinks by neutron irradiation, the presence of self stresses in the specimen and the dependence of the boundary conditions on neutron flux. A significant divergence is unlikely in practical cases, it requires a strength greater than is attainable in macroscopically strong solids. The existence of a Kirkendall effect is pointed out, together with the possibility of volume expansion. © 1969.