CREEP OF COPPER IN THE TEMPERATURE-RANGE 423-623-K

The creep of copper in the temperature range 423-623 K was investigate d and creep curves modelled by combining semi-empirical equations desc ribing deformation and damage. Previous work has indicated that in thi s temperature range there is a change in the creep behaviour which is usually ascribed to a change in deformation mechanism from power law c reep to power law breakdown. Evidence for this change comes mostly fro m measurements of steady state creep behaviour which does not account for the possibility of creep damage during testing. The purpose of thi s investigation is to demonstrate that if the creep curve is viewed as a whole, i.e. deformation and damage are considered simultaneously, t he transition in behaviour can just as well be described in terms of a single deformation mechanism with a change in the dominant fracture m echanism.