Exhaustion theory of creep in metals at low temperatures

Abstract

The theory of creep in metals at temperatures sufficiently low that dislocation climb is negligible has been examined for the case that strain is controlled by a set of exhaustible glide dislocation sources. The theory of Nabarro has been examined in detail for the rate limiting mechanism being the intersection of dislocations. The dependence of strain rate on stress, temperature, and the nature of the dislocation distribution at constant temperature and stress and following abrupt changes in stress and temperature has been derived. Expressions are presented which relate the strain rate to flow stress and parameters characterizing the dislocation distribution, and results are compared with experimental data for several close-packed metals.