Carbon-Kevlar intraply hybrid fabric polymer composites: mechanical performance

The emerging needs for lightweight structural materials with high performance eagerly await the hybridization of materials with high stiffness and toughness. Kevlar polymer composites protect against ballistic impacts and sharp objects but suffer from poor compressive strength and stiffness. This work attempts to hybridize Kevlar and carbon yarns in the fabrics used to fabricate the composite and evaluate the effects of carbon fiber hybridization on the mechanical performance of hybrid fabric composites. Intraply hybridized carbon-Kevlar (C-K) composite laminates are manufactured through a vacuum-assisted resin transfer molding process. Performance parameters, such as strength and failure limits, of the composites are experimentally evaluated under tensile, compressive, flexural, and low-velocity impact loading. Warp and weft, both directions, are considered for load application under each testing category, enabling the performance evaluation in longitudinal and transverse directions. Scanning electron microscopy is used to identify the breaking patterns and failure mechanisms of fibers, matrix, and overall laminates. The mechanical test results indicate that the hybridization pattern and direction of carbon yarn in the carbon-Kevlar hybrid fabric significantly affect the modulus and strength. The tabulated test data claim that elastic modulus increases by 30% equal to 10.18 GPa under tensile loading, flexural modulus by 29% equal to 36.9 GPa under three-point bend loading and the compressive strength by 57% equal to 166 MPa under compression loading geometry for C-K composites having carbon yarns in load direction when compared with the monolithic Kevlar composites. The results may indicate the suitability of C-K hybrid composites in structural applications that require high strength and optimal protection against ballistic impacts in defense and aviation sectors.

Automated summary

This research aims to evaluate the effects of carbon fiber hybridization on the mechanical performance of Kevlar composites. The results demonstrate that hybridization significantly enhances the modulus and strength of the composites. These findings suggest the potential suitability of carbon-Kevlar hybrid composites in structural applications that require high strength and ballistic protection.