Dynamical systems approach to the creep of metals population dynamics model

Abstract

A new mathematical description of the creep curve has recently been suggested, based on the concept of a damped dynamical system. The nature of the dynamical system was not stipulated, but it was suggested that it could be considered as the population of activation sites, the creep strain corresponding to the total number of sites activated. The creep curve should, therefore, be able to be considered in terms of population dynamics. This approach is considered in the present paper, where simple population dynamics models have been set up to show similar behaviour to that observed for decelerating rate and accelerating rate creep. The predictions of these models have been considered with reference to a modified 9Cr-1Mo steel, and it has been found that population dynamics concepts can be used to model much of the observed creep behaviour.