Braga, R. A Int. Journal of Engineering Research and Applications www.ijera.com ISSN : 2248-9622, Vol. 4, Issue 9( Version 1), September 2014, pp.174-184 www.ijera.com 174 | Page Rear Bumper Laminated In Jute Fiber With Polyester Resin. Braga, R. A¹; Magalhaes Jr, P. A. A. 2 1 FIAT Automóveis S.A., Teardown, CEP 32530-000, Betim, MG – Brasil 2 PUC–MINAS, Instituto Politécnico, CEP 30535-610, Belo Horizonte, MG – Brasil Abstract Today, a growing interest exists in the use of natural of fibers (sisal, coconut, banana, and jute), as reinforcement in composites. The aim of the present study is shows the use of jute fiber agglutinated with polyester resin in the automobile industry in the production of a rear bumper of hatch vehicle. A simplified mathematical model was used for evaluation of the flaw on trunk center cover submitted to dynamic loads. The traverse section of the referred bumper is simplified by a channel formation. This study shows that a rear bumper made using jute fiber agglutinated with polyester resin will be possible. The molded part obtained good visual characteristics, good geometric construction and surface without bubbles and imperfections in the fiber and resin composite. The mathematical model to failure criterion showed that the rear bumper in jute fiber will not resist to an impact equivalent at 4.0 km/h. Keywords: Natural fiber, Jute, Rear Bumper, Composites, Resin. I. INTRODUCTION The development of materials ecologically correct and a better adaptation of processes for using these materials are fundamental tools in the search of alternatives to minimize environmental problems in the world (Dotan and Al-Qureshi, 1996). The use of raw materials of renewable sources is being object of several studies and researches, due to the potential in the substitution of derived petro-chemistry materials (Al-Qureshi, 2002). The composites are materials consisting of two or more chemically distinct constituents, having a distinct interface separating them. One or more discontinuous phases therefore, are embedded in a continuous phase to form a composite (Geethamma, Thomas, Lakshminarayanan, and Sabu, 1998). The discontinuous phase is usually harder and stronger than the continuous phase and is called the reinforcement, whereas, the continuous phase is termed the matrix (Joshi, Drzal, Mohanty and Arora, 2004). Jute is a hydrophobic material and moisture absorption alters the dimensional and mechanical characteristics of jute fibers laminate (Mir, Zitoune, Collombet and Bezzazi, 2010), (Hachemane, Zitoune, Bezzazi, and Bouvet, 2013). The natural fibers present a great potential application in the automobile industry, especially in the internal covering of automobiles, bus and trucks. The future perspective for the use of natural fibers is very good also in other areas. For instance, the textile industry is now with expansion international market. In the last years, use of natural fibers as, coconut, sisal, rami, sugar-cane pulp, jute and pineapple as reinforcement in polymeric material had an accelerated growth. They are source of renewable natural resource (Braga, 2006). Natural fibers present low cost, are biodegradable, recycled, no poisonous and can be incinerated. They are being used as reinforcement in polymeric and substitute synthetic fibers partially as asbestos, Kevlar, boron, carbon, nylon and glass. In spite of these good mechanical characteristics, they present a high cost, are abrasive to the processing equipment’s, possess high density, generate products with very high recycling cost, besides some of those fibers commit human health (ASM, 2001). 1.1 Resins Matrices have as main purpose to transfer the stresses imposed on the composite material to the fibers, as well to serve as a support and protection of the fibers. Generally, composite matrices of thermosetting resins are used because they have great mechanical properties and dimensional stability. They are also resistant to chemical attack and have high thermal resistance (PIRES, 2009). According to Bento (2006) the matrix has three main functions which are:  To protect the surface of fibers from damage by abrasion that would lead to fracture;  Adhere in the surface in order to transfer the force has applied to the same fiber;  To separate the fibers each other in order to improve the resistance of propagation of transverse cracks to other fibers. 1.1.1 Synthetic resins Synthetic resins are resins widely used in industrial scale. Macromolecules are obtained through chemical reactions in reactors using the appropriate monomers. Depending on the resin the obtainment RESEARCH ARTICLE OPEN ACCESS