TY - CHAP AB - Nowadays, clinching is a widely used joining technique, where sheets are joined by pure deformation to create an interlock without the need for auxiliary parts. This leads to advantages such as reduced joining time and manufacturing costs. On the other hand, the joint strength solely relies on directed material deformation, which renders an accurate material modelling essential to reliably predict the joint forming. The formation of the joint locally involves large plastic strains and possibly complex non-proportional loading paths, as typical of many metal forming applications. Consequently, a finite plasticity formulation is utilised incorporating a Chaboche–Rousselier kinematic hardening law to capture the Bauschinger effect. Material parameters are identified from tension–compression tests on miniature spec- imens for the dual-phase steel HCT590X. The resulting material model is implemented in LS-Dyna to study the locally diverse loading paths and give a quantitative statement on the importance of kinematic hardening for clinching. It turns out that the Bauschinger effect mainly affects the springback of the sheets and has a smaller effect on the joint forming itself. AU - Friedlein, Johannes AU - Mergheim, Julia AU - Steinmann, Paul ID - 34211 KW - Clinching KW - Material modelling KW - Kinematic hardening KW - Parameter identification KW - Bauschinger effect SN - 2367-1181 T2 - The Minerals, Metals & Materials Series TI - Influence of Kinematic Hardening on Clinch Joining of Dual-Phase Steel HCT590X Sheet Metal ER - TY - CHAP AB - Force–displacement measurements and micrograph analyses are commonly used methods to validate numerical models of clinching processes. However, these methods often lead to resetting of elastic deformations and crack- closing after unloading. In contrast, the in situ computed tomography (CT) can provide three-dimensional images of the clinch point under loading conditions. In this paper, the potential of the in situ investigation of a clinching process as validation method is analyzed. For the in situ testing, a tailored test set-up featuring a beryllium cylinder for load-bearing and clinching tools made from ultra-high-strength titanium and Si3N4 are used. In the experiments, the clinching of two aluminum sheets is interrupted at specific process steps in order to perform the CT scans. It is shown that in situ CT visualizes the inner geometry of the joint at high precision and that this method is suitable to validate numerical models. AU - Köhler, Daniel AU - Kupfer, Robert AU - Troschitz, Juliane AU - Gude, Maik ID - 34212 KW - Clinching KW - Non-destructive testing KW - Computed tomography KW - In situ CT SN - 2367-1181 T2 - The Minerals, Metals & Materials Series TI - Clinching in In Situ CT—A Novel Validation Method for Mechanical Joining Processes ER - TY - CONF AB - The conduction of structure-borne sound through joints causes energy dissipation. The sound reduction index describes this energy loss as a level decrease in the particle velocity across series-connected damping elements for which the superposition principle applies. This simple model can help to develop a testing method for joints based on this characteristic energy loss. In this paper, this model is experimentally evaluated for multiple in-series clinched aluminium sheets. Samples connected by several clinch points arranged in parallel are investigated experimentally, and the results are discussed. AU - Stephan, Richard AU - Brosius, Alexander ID - 36462 KW - clinching KW - mechanical joining KW - damping KW - model KW - evaluation KW - dynamics T2 - The 28th Saxon Conference on Forming Technology SFU and the 7th International Conference on Accuracy in Forming Technology ICAFT TI - Experimental Measurement Method and Evaluation of an Analytical Approach for Sound Conduction through Multiple Clinched Sheets ER - TY - JOUR AU - Bielak, Christian Roman AU - Böhnke, Max AU - Beck, Robert AU - Bobbert, Mathias AU - Meschut, Gerson ID - 20678 JF - Journal of Advanced Joining Processes. KW - Clinching KW - process simulation KW - FEM KW - pre-straining KW - sensitivity analysis TI - Numerical analysis of the robustness of clinching process considering the pre-forming of the parts ER -