The multiaxial and uniaxial creep ductility of Type 304 steel as a function of stress and strain rate

Calculations of creep damage under conditions of strain control are often carried out using a ductility exhaustion approach. Issue 3 of the R5 procedure uses a ductility exhaustion approach to calculate creep damage, in which the ductility is a function of creep strain rate and temperature. However, recent studies have shown that the prediction of creep damage in creep-fatigue tests is improved when the creep ductility is considered to be a function of stress, creep strain rate and temperature. The aim of this paper is to describe the development of a new model for the effect of multiaxial states of stress on creep ductility which is intended for use with a creep damage model in which the creep ductility is a function of stress, creep strain rate and temperature.