Mechanical behavior of clinched sheet material joints and strength design procedure

Clinching is an effective joining technique for lightweight sheet materials that are difficult or impossible to weld. A theoretical model for clinched joints in metal sheets was established and a design method for improving joint strength by selecting different clinching tools was proposed. The analytic model is defined as a function of the neck-thickness and the undercut, which are the key parameters of joint geometry. Based on the analytic model, the design method of clinched joint strength that can satisfy required strength was proposed. Clinching experiments were conducted with 2.00 mm thick aluminium alloy 5052 sheets. Various conditions were used during the clinching process to validate the joint strength model. Tensile-shear strength of clinched joints was measured by a servo-hydraulic testing machine. The calculated joint strength was in good agreement with the experimental results.