Metal-composite joining using magnetic pulse crimping process: An effective manufacturing approach for AA1050-CFRP joint

Magnetic pulse crimping is a high-speed force-fit joining process that uses electromagnetic forces to plastically deform a conductive flyer tube onto a target, forming a permanent mechanical joint. In this manuscript, aluminum alloy AA1050 flyer tubes are joined with unidirectional pultruded Carbon Fiber Reinforced Polymer (CFRP) rods using an Archimedean spiral coil and a step-taper field shaper. The joint strength is evaluated using pull-out, compression-shear, leakage, and torsion tests, with the results also assessed by SEM, EDS, cross-sectioning, and micro-hardness testing. SEM results reveal that the joint was achieved through mechanical interlocking, with a wavy AA-CFRP interface and AA penetration into the carbon fiber reinforced polymer surface. All the joints are leak-tight at 6.5 bar. To support the physics of the high-speed process, analytical calculations are also carried out to determine the required magnetic field and associated magnetic pressure for the joining process. Furthermore, a fully coupled finite element simulation is also carried out using LS-DYNA and agrees with the experimental results. This work will be highly useful, providing detailed insight into the magnetic pulse crimping process for high-strain-rate joining of AA-CFRP across various applications.