Experimental study on warm roll bonding of metal/polymer/metal multilayer composites

The manufacturing of metal/polymer sandwich composites via roll bonding can offer great advantages over other techniques such as overmolding and injection molding, because those techniques are more complex and costly. Roll bonding of multilayer composites, however, is challenging due to significant differences in the mechanical properties and adhesion characteristics of polymeric and metallic materials. In this study, warm roll bonding (WRB) has been applied to fabricate a sandwich composite consisting of commercially pure aluminum (AL1100) and polyurethane (PU) sheets. The effects of WRB process parameters, which include surface roughness, preheat temperature, rolling speed, and total thickness reduction, on the adhesion strength have been investigated using the peel test. Mechanical interlocking was the primary adhesion mechanism in direct bonding of AL1100 and PU by rolling. An optimal surface roughness value was observed at 5.63 μm where the failure mode transitioned from adhesive to cohesive as the surface roughness increased. An optimum temperature and rolling speed were identified to be 200.2 °C and 29.7 rpm, respectively. The study showed a promising potential for applying WRB to mass produce metal/polymer hybrid composite panels.