Development and characterization of a polypropylene matrix composite and aluminum hybrid material

Hybridizing different materials, such as metals and polymer matrix composites, has recently drawn attention as it can produce a unique material that offers advantages from both the metals and the composites. However, the strict surface preparation required, a relatively low production rate, and the resultant weak interface have been the hurdles for this technology. The low surface energy of some polymeric materials, such as polypropylene (PP) and their composites, has posed even more challenges when bonding with metals. This work aims to develop a hybridized PP matrix composite and aluminum with through thickness reinforcements (TTRs) at a high production rate and with minimal treatment. Long glass fiber PP matrix composite (LFT glass/PP) is integrated with aluminum sheet using an extrusion–compression molding process at a rate of 2 minutes per plate. The bonding between these two materials is achieved using the TTRs on the aluminum sheet that provide mechanical locking at the interface. The hybridized aluminum and glass/PP LFT material is evaluated on its performance in lap shear, short beam shear, flexure, and tension. It is concluded that the mechanical locking at the interface provides a lap shear bonding strength of 6.8 MPa, and the hybridized material has significantly improved tensile and flexural modulus as well as strength compared to the glass/PP LFT only. The same approach can be readily extended to hybridizing other polymer matrix composites with metallic materials.