TY - JOUR T1 - Manufacturing and Investigating Mechanical Properties of Polymeric Composites Reinforced with Natural Fibers TT - ساخت و بررسی خواص مکانیکی کامپوزیت پلیمری تقویت‌شده با الیاف طبیعی JF - mdrsjrns JO - mdrsjrns VL - 19 IS - 1 UR - http://mme.modares.ac.ir/article-15-16765-en.html Y1 - 2019 SP - 75 EP - 83 KW - Composite KW - Mechanical Properties KW - Kenaf Fiber KW - Epoxy KW - Micromechanical Models N2 - By increasing the level of public awareness, more recyclable and natural materials are used. The aim of this research was to fabricate natural fiber reinforced composites and to investigate the effects of fiber length (5mm and 9mm), fiber mass percent (5%, 10%, 12.5%, and 15%), and fiber surface treatment on tensile, flexural, and water absorption properties of the fabricated composite. The experiments were designed, by the Taguchi method. In this research, epoxy resin and kenaf fiber have been used. Tensile, flexural and water absorption tests were performed on the samples. The highest values were 37.67 MPa for tensile strength, 4.94 GPa for tensile modulus, 31.78 MPa for flexural strength, and 6.05 GPa for flexural modulus. The lowest percentage of water absorption was 0.3%. Alkali treatment improved tensile, flexural, and water absorption properties. The optimum of fiber mass percent was 12.5% to maximize tensile strength, tensile modulus, and flexural strength, 10%to maximize flexural modulus, and 5% to minimize water absorption. Except for the tensile modulus, the effect of fiber length on the mechanical properties of the composite is observed to be less pronounced than the other two factors. To maximize the tensile modulus, the fiber length is better to be 9 mm. In this study, the values obtained for the tensile strength and tensile modulus of the fabricated composite are more than the ones in the previous works. Finally, the strength and tensile modulus obtained experimentally were compared with the ones obtained via two micro-mechanical models, modified rule of mixture, and modified Halpin-Tsia model. M3 ER -