Mechanical Interlock Made by Electromagnetic Crimping for Axial Load Resistance Using Aluminum Tube and Steel Rod

Abstract

Joining an aluminum tube with a steel rod using thermal-based welding processes like arc welding is challenging because of oxide formation, which requires a higher melting temperature than the parent metal. In this article, the electromagnetic crimping process is used to join the aluminum tube and a steel profiled rod mechanically. The circumferential double grooves, which have a rectangular shape, were machined on the steel rod with different geometrical parameters. Discharge energy of 4.7 kJ and a groove edge angle of 0.5 mm were kept constant. Therefore, the primary goal of this study is to investigate the effect of geometrical parameters on joint strength using a double rectangular groove. The result of the pullout test revealed that the joint strength of most crimped samples was found in the range of the strength of the aluminum tube. Based on the results obtained, a design guideline that describes the effects of the width-to-depth ratio on joint strength is proposed. Further, the effect of groove depth on the percentage of gap filling, wrinkling, and tube thickness reduction was studied in detail. Moreover, microhardness at the joint interface was also investigated.