A rectangular shear clinching process was applied to join two 1180 MPa ultra-high strength steel sheets having low ductility. In the rectangular shear clinching process, the sheets were joined with partial separation in the upper sheet. The sheets were joined by interlock between the upper and lower sheets with upper sheet separation in the short sides of a rectangle, whereas fracture was prevented in the long sides of a rectangle. The die shape was optimized in order to increase the interlock, and the sheets were joined. Then, the strength of the joined sheets by rectangular shear clinching was compared with that of welded sheets. The strength of the clinched sheets was smaller than that of the welded sheets in both the cross-tension and tension-shearing tests. The fatigue limit of the clinched sheets in the cross-tension test was smaller than that of the welded ones, while the limit in the tension-shearing test was larger. It was found that the rectangular shear clinching process without an airtight joint is effective in joining of the ultra-high strength steel sheets having low ductility and high flow stress.
Abe, Y., Saito, T., Nakagawa, K., & Mori, K. I. (2018). Rectangular shear clinching for joining of ultra-high strength steel sheets. In Procedia Manufacturing (Vol. 15, pp. 1354–1359). Elsevier B.V. https://doi.org/10.1016/j.promfg.2018.07.348