A Study on Tensile Shear Characteristics of Dissimilar Joining Between Pre-coated Automotive Metal Sheets and Galvanized Steels with the Self-Piercing Rivet and Hybrid Joining

Abstract

The automotive manufactures increase their use of lightweight materials to improve fuel economy and energy usage has a significant influence on the choice of developing materials. To meet this requirements manufacturers are replacing individual body parts with lightweight metals, for these the process treating and painting surfaces is changing. The pre-coated steels are newly developed to avoid the conventional complex and non-environmental painting process in the body-in-white car manufacturing. The development of new joining techniques is critically needed for pre-coated steel sheets, which are electrically non-conductive materials. In the present study, dissimilar combination of pre-coated steel and galvanized steel sheets were joined by the self-piercing rivet, adhesive bonding and hybrid joining techniques. The tensile shear test and free falling high speed crash test were conducted to evaluate the mechanical properties of the joints. The highest tensile peak load with large deformation was observed for the hybrid joining process which has attained 48% higher than the self-piercing rivet. Moreover, the hybrid and adhesive joints were observed better strain energy compared to self-piercing rivet. The fractography analyses were revealed that the mixed mode of cohesive and interfacial fracture for both the hybrid and adhesive bonding joints.

Parametric Investigation of Effect of Abnormal Process Conditions on Self-Piercing Riveting

“…Sun et al [9] and Haque et al [10] defined the cross-sectional characteristics that can alter the mechanical properties of the joint. Previous studies have discussed the joint characteristics according to various combinations such as Al/Fe [11,12], CFRP/metal [13], CFRP/steel/Al [14], clad steel/Al [15], and pre-coated steel sheets [16]. As the hardware elements of the SPR process, various combinations of rivet and die have been experimentally evaluated to investigate the effects of shape [17][18][19] and coating [20][21][22].…”