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Fibre metal laminates (FML) are being used in automotive, aerospace and naval applications due to their light weight and superior performance. The FMLs are made by sandwiching composite with metal. The environmental concerns due to non-biodegradability of such structures, lead to the development of FML containing natural fibre composites. Natural fibres composite, despite having good damping properties have overall poor mechanical properties. However, this aspect can be improved by weaving the fibres in 3 D pattern. In literature, FML made using 3 D woven jute composites is never reported. Furthermore, no literature is found on adhesion of natural fibre composite-metal bonding. In this paper, development of novel 3 D Jute Reinforced natural fibre Aluminium Laminates (JuRALs) is reported. Furthermore, the effect of 3 D weaving pattern and metal-composite bonding on mechanical properties and failure mechanism of the developed samples is also discussed in detail. The four-layered 3 D woven Jute fabric reinforcement was made using four interlocking patterns. The composites and JuRALs were fabricated using epoxy resin by vacuum infusion technique. The surface of aluminium was treated using phosphoric acid anodizing. Tensile, flexural and T-peel tests were performed according to ASTM testing method using Z100 All-round, Zwick Roell. The results showed that out of four types of used reinforcements, the through-thickness composites had better tensile properties while layer-to-layer composite had better flexural properties. The tensile and flexural properties of JuRALs made with through-thickness interlock reinforcement were better as compared to layer-to-layer interlock reinforcement. The T-peel results depicted that the constituent materials influenced the metal-composite adhesion properties, rather the type of 3 D structure.

Friction stir welding (FSW) is a quite recent welding method which takes advantage of being performed in the solid state. Compared with the usual welding processes, it therefore presents many benefits such as a lower heat-input, a reduction of residual stresses and an elimination of the solidification defects etc.. Up to now, it has essentially been applied to aluminium alloys and far more recently to a small number of bimaterials. The present study deals with three kinds of beads between pure copper and a 6082 aluminium alloy. Both materials were butt joined by FSW. The welds differ by the location of the tool which was placed either at the interface between the two metals or on the copper or the 6082 side of this surface. Their structure was characterized at a multi-scale level by using a number of techniques. Tensile and microhardness tests were also performed. The tool place is shown to govern the microstructure and the ensuing mechanical behaviour of the weld. Its influence on the plastic flow with its repercussions on i) welding defects and ii) mechanical properties is going to be demonstrated. Some ways of improvement of the welding process will finally be suggested.

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