The mechanical properties of fibre-metal laminates based on glass fibre reinforced polypropylene

This paper investigates the quasi-static and impact properties of a novel fibre/metal laminate system based on a tough glass-fibre-reinforced polypropylene (GFPP). Initial testing has shown that excellent adhesion can be achieved by surface treating the aluminium and incorporating an interlayer based on a maleic-anhydride modified polypropylene copolymer at the interface between the composite and aluminium plies. Single cantilever beam tests have indicated that the fracture energy of these systems is extremely high over a wide range of loading rates. Subsequent testing of a number of laminates has shown that the tensile properties of these layered systems are, as expected, strongly dependent on the volume fraction of composite. Low-velocity impact testing on three different stacking sequences has indicated that these materials offer excellent resistance to dynamic loading. In addition, an examination of polished cross-sections of the impact-damaged region have shown that the incident energy is absorbed through plastic deformation in the aluminium layers and localised micro-cracking within the composite plies.