Comparison of pin-loaded tensile behavior and failure behavior of thermosetting and thermoplastic composite

Abstract

This study investigated the pin-loaded tensile behavior, bearing strength, and failure mechanisms of thermosetting and thermoplastic composite materials. Specifically, the investigation focuses on carbon-fiber-reinforced polyetherketoneketone (CF/PEKK) and carbon-fiber-reinforced epoxy (CF/EPOXY). Notably, CF/PEKK exhibited a shear-out failure mode, surpassing CF/EPOXY with a 56.4% higher peak load. The absence of crack propagation in CF/EPOXY, attributed to the presence of yarn at a 90∘ angle, leads to bearing failure. In contrast, CF/PEKK demonstrates a significantly higher bearing strength, approximately 150[Formula: see text]MPa greater than CF/EPOXY. This discrepancy in performance suggests that CF/PEKK holds promise as a structural material for applications involving the fastening of thermoplastic composites, presenting a viable alternative to traditional thermosetting composites. The findings imply that the unique failure mechanisms and enhanced mechanical properties of CF/PEKK make it a compelling candidate for use in scenarios where thermosetting composites are conventionally applied. This study contributes valuable insights into the potential advancements and applications of thermoplastic composites in structural materials, paving the way for optimized and innovative engineering solutions.