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Composites: Part B
journal homepage: www.elsevier.com/locate/compositesb
Green composites: A review of adequate materials for automotive applications Georgios Koronis ⇑, Arlindo Silva, Mihail Fontul
Instituto Superior Tecnico, Mechanical Engineering Department, Lisbon, Portugal
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This study provides a bibliographic review in the broad ﬁeld of green composites seeking-out for materials with a potential to be applied in the near future on automotive body panels. Hereupon, materials deriving from renewable resources will be preferred as opposed to the exhaustible fossil products. With the technical information of bio-polymers and natural reinforcements a database was created with the mechanical performance of several possible components for the prospect green composite. Following the review, an assessment is performed where aspects of suitability for the candidate elements in terms of mechanical properties are analyzed. In that section, renewable materials for matrix and reinforcement are screened accordingly in order to identify which hold both adequate strength and stiffness performance along with affordable cost so as to be a promising proposal for a green composite. Ó 2012 Elsevier Ltd. All rights reserved.
Article history: Received 27 December 2011 Received in revised form 7 May 2012 Accepted 3 July 2012 Available online 24 July 2012 Keywords: A. Polymer–matrix composites (PMCs) B. Mechanical properties Natural ﬁbers
1. Introduction Green composites deriving from renewable resources bring very promising potential to provide beneﬁts to companies, natural environment and end-customers due to dwindling petroleum resources. The shift to more sustainable constructions in automotive industry is not only an initiative towards a more viable environment and cost efﬁciency but also a demand of European regulations. The latter are playing an important role as a driving force toward sustainable materials’ use. According to the European Guideline 2000/53/EG issued by the European Commission, 85% of the weight of a vehicle had to be recyclable by 2005. This recyclable percentage will be increased to 95% by 2015 . Another way to balance sustainability and cost is with the use of composites in automobile panels, as introduced by a number of automakers which use renewable materials in composites. Composites made of renewable materials have been rampantly used in interior and exterior body parts. Similar components are used as trim parts in dashboards, door panels, parcel shelves, seat cushions, backrests and cabin linings. In recent years there has been increasing interest in the replacement of ﬁberglass in reinforced plastic composites by natural plant ﬁbers such as jute, ﬂax, hemp, sisal and ramie [2–4]. A natural based material can be deﬁned as a product made from renewable agricultural and forestry feedstock, including crops and crop by-products and its residues. Although end-of-life directives and regulations will ask for components of higher recyclability, the use of renewable materials has not been dictated. Further ⇑ Corresponding author. Address: Instituto Superior Tecnico, Mechanical Building 2, Room 1.45, Av. Rovisco Pais 1, 1049-001 Lisbon, Portugal. Tel.: +351 926177071; fax: +351 218474045. E-mail address: firstname.lastname@example.org (G. Koronis). 1359-8368/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.compositesb.2012.07.004
market penetration of green composite will occur only when their production can be rendered cost effective and competitive to the present injection-molded thermoplastics used on many vehicles. Materials experts from various automakers estimate that an all-advanced-composite auto-body could be 50–67% lighter than a current similarly sized steel auto-body as compared with a 40–55% mass reduction for an aluminum...