Effects of Flat Energy Director Thickness and Welding Time on Interface Formation for Ultrasonic Welding of GF/PPS Composites

In this paper, the resin films were selected as energy directors, and the influence of flat energy director thickness and welding time on the ultrasonic welding joints of GF-PPS composites was investigated. The ultrasonic welding termination condition was set to time-control mode in order to analyze the influence of energy director thickness on the interface formation. The viscoelastic heat generation and interfacial temperature distribution of energy directors with different thicknesses during the welding process were analyzed using COMSOL software and a thermocouple. The interface and defect formation mechanisms were analyzed by examining the macro and microstructural characterization of the joint cross-section. The lap shear strength of joints under different welding parameters was evaluated through single lap shear tests, while the fracture mechanisms were analyzed using a scanning electron microscope. Furthermore, these findings can be extended to other types of composites, which provide valuable insights for improving the ultrasonic welding process of thermoplastic composites.