Fretting-contact-induced crack opening/closure behaviour in fretting fatigue

• Crack opening/closure behaviour during fretting fatigue of SUS316L was evaluated.
• Crack opening under compressive stress was found in experiment and FEA.
• Fatigue lives were predicted by consideration of crack opening.
• Predicted lives were in good agreement with the experimental lives.

Fretting fatigue experiments and finite element analysis of stainless steel (SUS316L) were performed to investigate the crack opening/closure behaviour of a fretting fatigue crack. The crack nucleated at the location of the maximum shear stress range and then propagated in the maximum tangential stress range direction. The crack path could be successfully predicted based on the criterion of the maximum tangential stress range. A crack opening under compressive bulk stress was found in both the experiment and finite element analysis. The crack opening was induced by the restraint of deformation of one side of the crack surface due to the fretting contact. The predicted fatigue lives without consideration of crack opening were significantly longer than those of the experimental results, while the predicted fatigue lives with consideration of crack opening were in good agreement with the experimental results.