Fiber-reinforced plastic composites (FRP) are widely utilized in various sectors due to their favorable mechanical properties. While the fiber reinforcement enhances the stiffness and strength of the plastics, it also results in a reduced elongation at break. As a result, the limited elongation has a negative effect on the energy absorption capacity and the structural integrity of the composite materials. Due to their lightweight and excellent mechanical properties, it is desirable to extend their use to energy absorption applications. A promising approach is to integrate ductile metal reinforcements into the FRPs. This study focuses on the development and characterization of hybrid composites (HVW) consisting of thermoplastic FRP (glass mat thermoplastic) and thin steel layers or narrow steel tapes. The incorporation of ductile steel allows the hybrid composite to act as an energy absorber for tensile loads. To achieve this, various parameters of the hybrid composite material are varied and their impacts are investigated. EN 1.4301 stainless steel is sandblasted and then pre-treated with primer and adhesion promoter. Quasi-static tests are carried out to characterize the composite configurations. Under quasi-static tensile loading, hybrid laminates exhibit a remarkable 14-fold increase in specific energy absorption. By enhancing the adhesion between the steel and the FRP, a cascade/ pseudo-ductile failure of the FRP can be achieved.
The integration of steel tapes opens up multifunctional applications for this hybrid material. In addition to its outstanding mechanical performance, hybrid FRP has the potential to be used for basic electrical functions such as grounding, signal transmission and shielding, which is beneficial for many applications.