Joining thin-walled structures without protuberance by two-strokes flattening clinching process

Clinching technology has better performance in joining different sheet materials. However, the protuberance and mechanical behaviors of clinched joints have always been needed to be improved. In this paper, a new clinching method, named two-strokes flattening (TFC) process, was proposed improve flatten protuberance. Mechanical testing including tension-shearing tests employed under quasi-static conditions evaluate between TFC conventional joints. The influences forming forces on response these were studied. static strength, energy absorption, material flow, failure modes investigated comparatively. experimental results demonstrated that tension-shear strength increased by 30.3% compared with at force 30 kN. Furthermore, flow analysis showed thickness interlock 79% 45.9%, respectively. absorption joint 82%. addition, process did not change mode joints, all neck fracture.