Simulation and experimental investigation on electromagnetic riveted joints with prefabricated cracks

This work developed numerical models for electromagnetic riveted (EMR) joints with and without prefabricated cracks, investigating the effect of pre-existing microcracks on EMR performance and failure mechanisms. Results showed that hole wall exhibited sudden late-stage stress increases for joints without prefabricated cracks. Stress intensified with decreasing distance from cracks for joints with prefabricated cracks, causing significant stress concentration. Positions farther from cracks in joints with prefabricated cracks had late-stage strain rate rises due to non-coplanar crack locations and interactive stress. Both joint types displayed high-strain-rate deformation. joints with prefabricated cracks had lower deformed tail heights, indicating higher punch impact velocity, strain rate, and greater energy dissipation. The numerical model was validated by experimental rivet tail height measurements and cross-sectional deformation comparisons, ensuring reliability.