Linear matching method on the evaluation of plastic and creep behaviours for bodies subjected to cyclic thermal and mechanical loading

This paper extends the previous Linear Matching Method (LMM) to allow for the evaluation of plastic, creep and ratchet strains of structures subjected to a general load condition in a steady cyclic state. The constant and varying residual stress fields associated with differing mechanisms as well as the steady cyclic stress state of the whole component are obtained for further structural design and assessment. The total strain range for use in fatigue assessment, including the effects of creep and plastic strains are obtained. A typical example of 3D holed plate subjected to cyclic thermal load and constant mechanical load are assessed here in detail to verify the applicability of the proposed numerical technique. The LMM results in the paper are compared with those by ABAQUS step-bystep inelastic analyses and demonstrate that LMM have both the advantages of programming methods and the capacity to be implemented easily within a commercial finite element code, in this case, ABAQUS. The LMM provides a general-purpose technique for the evaluation of creep/ fatigue interaction.