Modelling of Thermomechanical Fatigue Stress Relaxation in a Single-Crystal Nickel-Base Superalloy
2014 (English)In: Computational materials science, ISSN 0927-0256, Vol. 90, 61-70 p.Article in journal (Refereed) Published
The thermomechanical fatigue (TMF) stress relaxation of the single-crystal nickel-base superalloy MD2 has been analysed and modelled in this paper. In-phase and out-of-phase TMF experiments in the nominal , and  crystal orientations have been performed. The TMF cycle consists of two loadings each with a 100 h long hold-time. A simple crystallographic creep model, based on Norton’s creep law, has been developed and used in conjunction with a crystal plasticity model. The model takes anisotropy and tension/compression asymmetry into account, where the anisotropic behaviour is based on the crystallographic stress state. The values of the creep parameters in the anisotropic expression were determined by inverse modelling of the conducted TMF experiments, a parameter optimisation were performed. The developed model predicts the stress relaxation seen in the TMF experiments with good correlation.
Place, publisher, year, edition, pages
Elsevier, 2014. Vol. 90, 61-70 p.
single-crystal superalloy, thermomechanical fatigue, creep, stress relaxation, anisotropy, parameter optimisation
IdentifiersURN: urn:nbn:se:liu:diva-107983DOI: 10.1016/j.commatsci.2014.04.009ISI: 000336656200009OAI: oai:DiVA.org:liu-107983DiVA: diva2:728485