Fatigue strength evaluation of self-piercing riveted Al-5052 joints under different specimen configurations

• We evaluate the monotonic and fatigue strengths of SPR joints.
• A prediction of the fatigue lifetime of a SPR joint is proposed by adopting the equivalent stress intensity factor.
• Fatigue crack initiation in a SPR joint occurs due to fretting damage.

In this study, static and fatigue tests were conducted using coach-peel, cross-tension and tensile–shear specimens with Al-5052 plates for evaluation of the fatigue strength of the SPR joints. For the coach-peel, cross-tension and tensile–shear geometries, the ratios of the fatigue endurance limit to static strength were 11%, 14% and 34%, respectively, assuming fatigue cycles of 106 for an infinite lifetime. The equivalent stress intensity factor range can properly predict the current experimental fatigue lifetime. Fatigue crack initiation occurred due to fretting damage between the upper and lower sheets and between the rivet and these sheets.