Influence of Welding Temperature and Weathering on Inductive Welded Hybrid Joints Made of Steel and TP-FRPC

Aim of this study is to investigate the influence of welding temperature and weathering on bond strength of induction welded hybrid joints made of steel and thermoplastic fiber reinforced polymer composites (TP-FRPC). The used TP-FRPC are continuous glass fiber reinforced-polyamide 6 (PA6), -polypropylene (PP), -polycarbonate (PC) and-polyphenylenesulfide (PPS). The metal sheets are mild steel (1.0338 and 1.0330). The surface pretreatments of the metal sheets are either laser structuring in line pattern, perpendicular to the load direction, or two different types of functional coating adhesives (Köratac HL 400 and Köratac HL 403) currently used in coil-coating processes. First the process parameters were optimized for each material combination by investigating the bond strength at different welding temperatures. In a second step, for each material combination, specimens were welded using the determined welding temperatures with the highest bond strength in order to investigate the influence of weathering on hybrid joints. Therefore the cataplasma test (DIN EN 13523-27: 2009) as well as alternating climatic change (BMW PR 308.2) were used.