Effects of Service Temperature on the Mechanical Properties of CFRP/Aluminum Alloy Self-Piercing Riveting Joints

Abstract

The effects of service temperatures on the mechanical properties of self-piercing riveting (SPR) joints of carbon fiber reinforced polymer (CFRP) sheets and AA5754 aluminum alloy sheets were investigated in this study. Three different thicknesses of 0°/90° lay-up sequences of CFRP sheets and aluminum alloy sheets were selected for the SPR joints, and these three joints were subjected to static tensile tests at four different temperatures of 25 °C, 50 °C, 80 °C and 125 °C. A noncontact strain measurement DIC-3D system was used to record changes in the strain field and scanning electron microscopy (SEM) was used to observe the failure area at the rivet hole of the CFRP sheet to study the damage forms and mechanisms of the joints. The results of the tests showed an average reduction of 35.4% in maximum load and an average degradation of 21.9% in energy absorption for the three joints at 125 °C compared to room temperature conditions.