Abstract: The mechanism of mechanical properties of Self-piercing Riveted (SPR) joints of aluminum alloy 5052 sheet with three rivets was investigated by experiments. The static and fatigue experimental data of m-o SPR joint (m-o joint) and m-I SPR joint (m-I joint) were obtained. The effectiveness of the experimental data was tested by normal distribution and two-parameter Weibull distribution. The best-fitting straight line of fatigue lift and two-parameter power function equations of fatigue load-fatigue life curves were acquired by least square method. Results show that the static fatigue failure modes of the SPR joint are the pull-out and fracture of the lower sheet respectively. The static strength, capacity of deformation and energy absorption, fatigue life and their stability of SPR joints with multiple rivets are all influenced by the distribution structure of the rivets. The m-I joints have favorable static property, but the m-o joints have excellent fatigue property overall. During the fatigue test, the sequences of the primary and secondary load bearing are generated by the distribution structure of rivets, and the fatigue fracture surface is the location of the primary load bearing sequence.

Key words: materials synthesis and processing technology, multiple-rivet, fatigue life, coefficient of variation, fractographic analysis