Abstract
Sisal fibers are one typical type of natural fibers that are currently being looked at as alternatives to inorganic fibers to be used as reinforcements on polymer matrix composites (PMCs). Natural fiber reinforced plastic (NFRP) composite materials are generally sought after by manufacturers because of their sustainability, biodegradability, low cost and mechanical characteristics. In this work, sisal fibers that were extracted from the Agave Sisalana plant are used to reinforce a polyester-based resin using a molding technique at low pressure resulting in a cross ply bio-composite laminate with around 25% Fiber Volume Fraction (FVF). Static tests were carried out on specimens that were cut from these laminates and the results showed that the ultimate tensile strength is found to be around 47 MPa. Displacement control and constant amplitude fatigue tests were then carried out at three different levels with a frequency of 5Hz. The fatigue tests results are extensively analyzed using stiffness degradation behavior, S-N curve diagrams, hysteresis loops and energy dissipation versus number of cycles. The fatigue endurance limit (over one million cycles) for these materials is achieved at a stress level of 55% of ultimate displacement. The implication of this work is that the use of these materials in areas such as car and aircraft interiors promises to significantly reduce weight, cost and carbon footprints without sacrificing performance.