Mechanical and thermal properties of flax/carbon/kevlar based epoxy hybrid composites

AbstractIn recent years, awareness on environmental issues has led to development of biobased materials for a variety of engineering structural applications. Nowadays, researchers and scientists are focusing their efforts on the development of sustainable materials that make use of readily available, renewable, and biodegradable natural resources. While significant progress has been made in the study of hybrid fiber reinforced composites, the fundamental problem of incorporating and selecting the optimal combination of reinforced fibers for various applications has not been adequately addressed. Hence present study addresses the use of combination of two natural fibers with different synthetic fibers to assess the performance of the hybrid fibers composites to develop for engineering applications. In present work the effect of stacking sequence on the mechanical and thermal property of the flax, kevlar, carbon and carbon‐kevlar hybrid fiber reinforced epoxy composites are studied. The four layered composite laminates with different stacking sequence were fabricated using hand layup technique to study the mechanical properties such as tensile, flexural, interlaminar shear, and impact tests, thermal behavior, water absorption, contact angle measurement and scanning electron microscopy. The hybrid carbon/flax composite (CFFC) had better strength as compared to KFFC, HFFC, and FFFF composite laminates with better tensile strength (178.48 MPa), tensile modulus (2132 MPa), flexural strength (378.86 MPa), flexural modulus (15.76 GPa) and interlaminar shear strength (13.91 MPa) and impact strength (13.86 MPa) and water absorption behavior. The stacking sequence revealed that the hybridization of the flax with the synthetic fiber enhanced the properties as compared to the pure flax composites. The influence of the synthetic fibers at outer skin layer had the effect on enhancing the properties of composites. From the obtained results we can effectively utilize the hybrid flax fibers in some various lightweight engineering applications.