Numerical and experimental investigation of impact strength and fracture mechanism of Kevlar and Hemp elastomeric thin biocomposite laminate under high-velocity impact: A comparative study

Abstract

Thin composite structures reinforced with woven fabrics are widely used in many industrial sectors due to their lightweight, easy access, and high specific performance. Due to safety, the study of fracture mechanisms and energy absorption of thin composite structures is significant. In this study, Kevlar and Hemp elastomeric thin biocomposite laminates with an elastomeric matrix filled with natural lignin filler with a low carbon footprint and with the aim of the sustainability concept of environmental protection have been designed experimentally and numerically for testing under high-velocity impact. The impact resistance of elastomeric composites reinforced with natural fillers is less reported. Good interaction of lignin-filled elastomeric matrix with woven hemp fabric is expected to show impact performance comparable to Kevlar-reinforced composites. For this purpose, Kevlar and hemp thin elastomeric biocomposites are tested under high-velocity impact with almost the same surface density. Also, tensile and dynamic compression tests (Hopkinson test) were performed to check the mechanical properties of the elastomer layer. The proposed laminates' penetration resistance and fracture behavior during an impact according to the Kevlar and hemp fabric constituent material model and the user-defined material model (VUMAT) for the nonlinear behavior of elastomeric materials considering the damage criterion in ABAQUS/Explicit confirmed. The results show, In the thin elastomeric hemp biocomposites, the tensile failure and stress transfer to the surrounding bundles cause more yarns to participate in the load-carrying process. As a result, the low penetration depth and more significant protection margin in fully green hemp composites provide impact performance comparable to Kevlar elastomeric composites.