Assessment of crack-tip fields of thermo-mechanical elastoplastic fatigue crack growth.

The present paper computationally investigated and characterized thermo-mechanical crack-tip fields under elastoplastic fatigue crack growth. The Δ J -integral is generally path-dependent and its far-field value is introduced to describe the singular crack tip field under considering thermo-mechanical loading influence. The influence of crack closure in fatigue crack growth is studied and quantified for thermo-mechanical fatigue crack growth. It confirms that the incorporation of temperature cycling does not affect the solution form of the crack-tip field dominated by Δ J eff , in analogy to an isothermal fatigue crack. However, the singular crack stress and the far-field effective Δ J eff for TMF are affected by the phase angle of the thermo-mechanical loads. • The crack-tip field in the closing process can be uniquely characterized by Δ J eff,far . • The TMF Δ J -integral is an increasing function of the path size in the plastic zone. • Δ J variations imply a higher driving force under IP TMF than that under OP TMF. [ABSTRACT FROM AUTHOR]