On the sensitivity of ultrasonic welding of epoxy- to polyetheretherketone (PEEK)-based composites to the heating time during the welding process
Eirini Tsiangou, Julian Kupski, Sofia Teixeira de Freitas, Rinze Benedictus, Irene Fernández Villegas
Abstract
This study aims at assessing the sensitivity of the ultrasonic welding process for joining epoxy- to thermoplastic-based composites sensitivity to the heating time. For that, carbon fibre (CF)/epoxy adherends with a co-cured PEI coupling layer were ultrasonically welded to CF/polyetheretherketone (PEEK) adherends at different heating times. Process-induced changes in the meso and microstructure of these welds were identified and correlated to the weld strength. Subsequently, a processing interval, i.e., a range of heating times resulting in less than 10% decrease of weld strength, was defined. As, expected, the dissimilar composite welded joints were more sensitive to the heating time than the CF/PEEK to CF/PEEK welded joints. However, this effect was less pronounced than expected, since a relatively wide processing interval could be obtained provided that the coupling layer had a sufficient thickness.