STUDY OF TENSILE BEHAVIOR OF THERMOPLASTIC FIBER METAL LAMINATES S.Suresh Assistant Professor, Velammal Engineering College, Chennai-66 deva.suresh78@gmail.com S.Ranganathan Final year student, Velammal Engineering College, Chennai-66 Abstract - Fiber–metal laminates (FMLs) have been used in a wide variety of applications in electronics, automotive, defence and aerospace industries. The recent need to develop a new range of materials has resulted in the development of high performance lightweight structures with excellent properties under tensile, flexure and impact conditions. Lightweight thermoplastic-based fiber–metal laminates were developed based on glass fiber (GF), polypropylene (PP) and an aluminum (Al) alloy materials. Metal– composite systems consist of alternating layers of metal and fibre-reinforced polymer composites which are bonded by an adhesive layer known as polypropylene grafted maleic anhydride. In this work, adhesion at the metal/composite interface has been achieved by the surface pretreatment of ‘Al’ with amino based silane coupling agent and incorporation of polypropylene based adhesive film such as polypropylene modified maleic anhydride (PP-g- MAH). This study investigates the tensile behavior of the FMLs under tensile loading condition at various weight percentages of PP-g-MAH such as 5%, 10%, 15% and 20% with PP. The results show that the increase in PP-g-MAH weight% improves the tensile performance of fiber metal laminates. Keywords: Fiber metal laminates, Tensile behavior, maleic anhydride, film stacking I. INTRODUCTION Recently, new types of FMLs are emerging as a result of the demand for more efficient and lightweight materials for use in the automotive and aerospace industries. They combine both the good characteristics of metals such as ductility, impact and damage tolerances with the benefits of fiber composite materials such as high specific strength, high specific stiffness and fatigue resistance. FMLs also offer the distinct advantage that production times can be greatly reduced, since it is only necessary to heat the thermoplastic to its processing temperature before rapidly cooling it to ambient conditions. Cortes and Cantwell (2004) investigated the tensile and fatigue properties of a novel fiber–metal laminate based on a titanium alloy and carbon fiber- reinforced poly-ether-ether-ketone (PEEK). Reyes and Cantwell (2000) investigated the mechanical properties of a glass fiber-reinforced polypropylene FML and found that this system offers excellent mechanical properties and an ease of repair, due to the thermoplastic nature of the matrix. G. Reyes (2006) developed Lightweight thermoplastic based fiber–metal laminates based on self-reinforced and glass fiber-reinforced polypropylene composite materials and revealed that the self-reinforced thermoplastic based fiber–metal laminate exhibits excellent forming properties. Demjen et al. (1999) focused on the mechanism of interaction between the silane coupling agents and the polypropylene matrix. They showed that amino functional silanes bond strongly to the surface of the matrix. Glass fiber-reinforced polypropylene (GFPP) is of particular interest due to its relatively low cost. PP is generally hydrophobic and shows low surface free energy and presenting serious adhesion difficulties bonding to other materials, even to polar materials, which has so far limited the widespread use of PP under mass production conditions. For this reason, a modification of the surface is necessary to produce well-adhering compounds. With regard to the PP composites, it can be said that the interphase control can be conducted with a silane coupling agent and a binding agent such as maleic anhydride into matrix PP. Silane coupling agents are generally considered to chemically react with both substrate and adhesive, so forming a system of covalent bonds across the interface, which is both strong and durable. Silane coupling agents with three alkoxy groups are the usual starting point for substrate modification. One end has an organo-functional group that is