Innovative Metal–Polymer Composite Panels with Integrated Channels for Thermal Management Systems Using Hybrid Friction Stir Channeling—HFSC

In this research, we assess the feasibility of employing hybrid friction stir channeling (HFSC) to produce composite panels that combined an 8 mm thick AA6082-T6 aluminum alloy and 5 mm thick glass-fiber-reinforced Noryl GFN2. HFSC is an innovative solid-state technology that combines both friction stir joining and channeling characteristics, which enable the generation of integral internal channels while joining different components. A parametric study was outlined to explore the effects of the travel speed, probe length, and tool plunging on the resulting composite panels. The resulting composite panels were subsequently subjected to a comprehensive analysis encompassing exterior ceiling quality, internal channel, and joining interface morphology. Depending on the processing parameters, the geometry of the channels was found to be quasi-rectangular or quasi-trapezoidal, with significant variability on cross-sectional area, resulting in hydraulic diameters ranging from 1.2 to 2.9 mm. The joining interface was characterized by a concavity of aluminum that was extruded downwards into the polymeric molten pool, which was clinched after polymeric re-solidification. The experimental results prove the ability to join metals and polymers while creating an integral channel in a single process step using HFSC. Despite the positive effect of irregular shaped channels on heat exchange, the numerical models evidenced a detrimental effect of 14.3 and 16.3% on ultimate tensile and flexural loads, respectively. This way, this fabrication technology evidenced promising characteristics that are suitable for manufacturing thermal management systems such as conformal cooling for plastic injection molding or battery trays for EVs.