Clinching and Torsional Ultrasonic Welding - An Innovative Process Combination for Joining Metal-Polymer Hybrid Structures

Due to the optimized local material adaption by using multi-material-structures, the final part properties can reach maximized performance and efficiency. This fact correlates with a rising demand for processes which join dissimilar materials (e.g. metal-polymer, thermoplastic-thermoset or incompatible thermoplastics) reliably. The present study deals with an innovative process combination of clinching and hot-melt adhesive bonding for joining fiber-reinforced polyamide (PA6-GF30) to steel. The energy input for the hot-melt adhesive bonding is performed by torsional ultrasonic welding. The study was aimed to analyze design variations of the ultrasonic weld seam to reach steady joint properties in spite of unsteady manufacturing conditions and to minimize interactions between clinching and ultrasonic welding. However, the hot-melt adhesive bonding process has always to keep the geometric preconditions for the following clinching process.