Effect of Fiber Orientation on the Mechanical Properties and Fracture Characteristics of Date Palm Fiber Reinforced Composites

The mechanical properties and fracture surface morphology of date palm fiber (DPF) reinforced polyester resin composites were investigated. Laminates with different orientation and volume fraction of reinforcement were prepared using resin transferred molding (RTM) processing technique. The fracture surfaces and sections through the molded composites were examined by means of scanning electron microscopy (SEM). Mechanical properties such as tensile strength, tensile modulus, ultimate elongation, the critical stress intensity factor (KI), and the crack fracture initiation energy (GIC) of composites prepared with different volume fraction of unidirectional and woven DPF reinforcement were calculated. The average tensile strength ranged between 55.2 and 86.1 MPa for long unidirectional fibers and up to 76.9 MPa for woven fibers. Incorporate, 60% volume fraction of the date palm fiber decreased the impact toughness of the unreinforced polyester matrix by 10%. Close SEM inspection showed that fiber pull-out, inter-laminar failure, and delamination were the major features of reinforced composites failure.