Thermo-Mechanical Fatigue Life Prediction Method in Terms of Energy

Abstract

Thermo-mechanical fatigue (TMF) problems are encountered in many industries, such as aerospace, power generation, mechanical engineering etc. The last decade has seen increased effort on modelling material behaviour under high operating temperatures and severe TMF environments. One of the current problems is formulation of the method allowing the design and evaluation of engineering systems operating under TMF conditions. In the literature few thermo-mechanical models have been presented. However, none of them has given satisfactory results for all thermo-mechanical loading histories. Life prediction models for TMF generally take the form:

• (1) frequency-modified strain-life or stress-life approaches [1–3];

• (2) parametric damage approaches [4–7];

• (3) continuum damage approaches [8–9];

• (4) damage rate approaches [10–12] including microcrack propagation models [13].