Structural Behavior Of Thermoplastic Welded Single-lap Shear Joints With Recycled Core Material

Abstract

Composite single-lap shear joints made from virgin plies and recycled core material are manufactured via induction and conduction welding using T300/polyphenylene sulfide (T300/PPS) as well as T700/low-melt polyaryletherketone (T700/LM-PAEK). The specimens are tested in quasi-static conditions to evaluate their mechanical performance and damage growth. Digital image correlation and high-speed cameras are used to capture the specimen behavior until after failure. While joints with recycled core material show a lower load-transferring capacity than their virgin counterparts (reduction of 13.8% for T300/PPS and 41.2% for T700/LM-PAEK), they are nonetheless an appealing option for applications where sustainability is a priority. Damage in virgin thermoplastic welded single-lap shear joints grows along the weld line. Conversely, specimens containing recycled core material may also experience delaminations between the core and the virgin outer plies. This suggests that thermoplastic welding can create interfaces with higher fracture toughness properties than those achieved during the consolidation of the base laminates.