Modelling of Complex Load Cycles at Elevated Temperature

Engineering components such as those found in high temperature plant applications are often subjected to cycles during which both stress and temperature change. These cycles can occur during normal service or during start-up/shut-down cycles and can significantly limit service lives of the components. Due to thermal gradients associated with heating and cooling, these load/thermal cycles are complex in nature and the cycle frequency is typically lower than that of a normal thermo-mechanical fatigue (TMF) cycle resulting in deformation dominated by creep mechanisms. The aim of this project is to develop a model for the deformation and damage that occurs during these complex cycles. A constitutive model which accounts for the effects of stress and temperature changes on material hardening and damage will be implemented within finite element (FE) software allowing predictions of component behaviour to be made.

This PhD project will be part funded by Schmidt+Clemens (SC) who will be able to provide expertise and data to validate and verify the numerical models.