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This paper investigates the room temperature formability of a fibre metal laminate system comprised of aluminium and a self-reinforcing polypropylene composite. Blanks of varying geometry were stretch formed over a hemispherical punch in a custom built stamping press. A real-time three-dimensional photogrammetric measuring system was used to acquire the evolution of surface strain and the strain at failure during forming. The results from this work illustrate that these advanced light weight material systems are amenable to mass production through stamp forming. A significant finding from this work is that these material systems can exhibit forming characteristics that are comparable and sometimes superior to metal forming.

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This paper investigates the effect of process parameters such as Blank Holder Force (BHF) and Feed Rate, on the spring back behavior of a polymer metal laminate (PML) system comprised of aluminum and polypropylene. Specimens were formed over a hemispherical punch in stamp forming process. A novel real time strain measuring system, ARAMIS, was employed to capture the strain evolution during forming. The results of this work indicate that both BHF and feed-rate exert influence in PML spring back behavior. Fundamental correlation between strain evolution during spring back and the shape of the finished part will be presented. A major finding from this work is that aluminum dominates the spring back behavior of PML in stamp forming.

Fibre metal laminates are sandwich materials comprised of a fibre-reinforced composite and a metal alloy. These advanced materials offer superior properties compared to the monolithic constituents; primarily, improved specific strength and stiffness compared to metals and improved impact and fatigue resistance when compared to composite materials. The use of these advanced materials is currently restricted to specialised applications where the superior properties justify the high cost of manufacturing. The formability of a fibre metal laminate based on a glass fibre reinforced polypropylene and an aluminium alloy is investigated in this study using techniques developed for the evaluation of metallic materials. Specimens of varying geometry were stretched over a hemispherical punch and an open die configuration was used to facilitate the acquisition of the strain using a using an optical measurement system. The experimental results were used to determine a forming limit diagram and to elucidate the safe forming limits of the material. In addition, the effect of specimen geometry on deformation behaviour was investigated by analysing the evolution of strain on the surface of the specimens. A significant finding of this study is that advanced materials such as fibre metal laminates can be formed in a similar manner to monolithic metals.