High temperature design remains an issue for many components in a variety of industries. Although finite element analysis for creep is now an accessible tool, most analyses outside the research domain use long standing and very simple constitutive models - in particular based on a power law representation. However, for many years it has been known that a range of materials exhibit different behavours at low and moderate stress levels. Recently studies of the behaviour of high temperature structures with such a stress range dependent constitutive model have begun to emerge. The aim of this paper is to examine further the detailed behaviour of simple structures with a modified power law constitutive model in order to instigate a deeper understanding of such a constitutive model's effect on stress and deformation and the implications for high temperature design. The structures examined are elementary - a beam in bending and a pressurized thick cylinder - but have long been used to demonstrate the basic characteristics of nonlinear creep.
- stress range dependent constitutive model
- structural analysis
- high temperature design