Innovative, high-performance, and cost-effective hybrid composite materials for crashworthiness applications

Integrating thermoset and thermoplastic materials in a single structure is a fascinating approach, especially when looking for optimized performance characteristics. These advanced hybrid structures can achieve levels of efficiency, strength, and resilience that are simply not attainable when using a single material type. Subsequently, this work aims to examine the deformation behavior and crashworthiness performances of square glass fiber-reinforced epoxy (GFRE) composite tubes filled with 3D-printed polylactic acid (PLA). To achieve this, three key 3D printing design parameters, that is, infill pattern structure, infill density, and layer height, were varied, each at four levels. The hybrid structures were subjected to quasi-static lateral compression. For the tested tubes, the crashing load and energy absorption responses were recorded against displacement, and failure modes were analyzed. The most effective parameter combination was identified using the complex proportional assessment (COPRAS) approach and compared to the performance of empty GFRE tubes. Additionally, a cost ratio parameter was intended to evaluate the economic feasibility of the designed tubes. The analysis concluded that the GFRE-H30/0.20 configuration offers the best combination of crashworthiness performance and cost efficiency.