Characterization of crack-tip fields for elastoplastic fatigue crack growth Part I: Analysis of the ?J-integral

In the present paper, the crack-tip field of elastoplastic fatigue crack growth without crack closure is computationally confirmed to possess the known HRR solution form, where the stress distributions are controlled by the AJ-integral. However, the plasticity-induced crack closure from fatigue crack growth changes the crack characterization dramatically and destroys the known singular crack-tip field form. While AJ shows the significant path dependency in the plastic zone, only the effective stress ranges in the unloading process can be controlled by the far-field effective AJ-integral. Fatigue crack growth can be characterized by the effective AJ-integral, with a smaller dominance zone than the conventional HRR zone.

Automated summary

This paper computationally confirms that the crack-tip field of elastoplastic fatigue crack growth without crack closure possesses the known HRR solution form, but the plasticity-induced crack closure dramatically changes the crack characterization. The effective AJ-integral can be used to characterize fatigue crack growth with a smaller dominance zone than the conventional HRR zone.