Delamination Characteristics of Aluminum-Composite Bonds: Impact of Reinforcements and Matrices

Adhesion properties of metal-composite bonds are crucial in defining composite capability with other metallic components, and failures could lead to severe accidents. Hence, the study is aimed at the development and characterization of metal-composite bonds using different rigid adherends and adhesive materials (thermoset and thermoplastics). Among natural fibers, jute was used, while aramid, carbon, and glass woven reinforcements were employed from synthetic fibers. A simultaneous comparison of both thermoset and thermoplastic matrices was done using epoxy, polypropylene (PP), and polyvinyl butadiene (PVB) as adhesive materials. Floating roller delamination characterization proved variation in adhesion qualities governing different failure modes by varying adhesive even in a single rigid adherend. The highest fracture toughness was observed for aluminum-jute bonds made with PP and PVB that was due to toughness of matrix and intralaminar failure. Carbon being brittle in nature showed the most fluctuated performance with a 90% difference between the highest value of carbon-PVB and the lowest value of carbon-epoxy. Thermoplastic matrices owing to plasticity offered overall more fracture toughness than brittle thermoset resin. Furthermore, intralaminar was the dominant failure mechanism in the jute-based bond made with thermoplastic matrix.