Feasibility study on hybrid weld-bonded joints using additive manufacturing and conductive thermoplastic filament

This work aims to explore innovative joining processes for additively manufactured components, and, in particular, to assess the feasibility of hybrid weld-bonded joints by comparing their performance with the baseline bonded and welded joint configurations. The novelty of the proposed solution lies in the fact that welding is achieved using a 3D printed material with conducive filaments, a solution derived from the use of embedded 3D printed circuits (direct printing) in the AM components. Direct printing can be used to obtain an accurate local control of the thermal cycle and to overcome geometrical limitations inherent to the process, as for example the need of access for the welding tools. The feasibility of the hybrid weld-bonded joint was assessed and, while for adhesive bonding the use of dedicated surface treatments was found to be necessary to improve the joint performance, the welding process was determined to be the most promising joining process, especially when directly integrated into a mull material additive manufacturing (MMAM) process.