%0 Journal Article %T Natural Fibers and Filler Materials Used in Glass Fiber Reinforced Polyester (GFRP) Composite Materials %A Recep £żLHAN %J - %D 2019 %X With the development of technology, composite materials have been developed due to the inadequacy of the pure materials and the usage areas have increased with time. Glass fiber reinforced polyester (GFRP) composite materials have widespread use in the world due to their properties such as good mechanical strength, elasticity, high corrosion resistance and economy. For this reason, it is aimed to improve material properties by adding different reinforced and filler materials to GFRP composites. In this study, the effects of using different materials such as sisal, jute, kenaf etc. different natural fiber reinforcement and glass beads, graphite, alumina etc. different filler material on the properties of GFRP composite materials were investigated. In the first part of the work, the information was given on natural fiber reinforced polymer composites in general. In the second part of the study, studies were given to investigate the effect of natural fiber reinforcement and filler materials used in GFRP composite materials on material properties. In these studies, natural fibers and fillers can be successfully incorporated into GRFP composite materials by different production methods, they can improve the material properties and reduce the cost %K Cam elyaf takviyeli polyester %K do£żal elyaf %K dolgu maddesi. %U http://dergipark.org.tr/ecjse/issue/45543/519072