Effect of Natural Fibre-epoxy Plies on the Mechanical and Shock Wave Impact Response of Fibre Metal Laminates

Anand Pai1

Adithya R Kini1

Chandrakant R Kini1

Satish Shenoy B1, Email

1Department of Aeronautical and Automobile Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India-576104

Abstract

Fibre metal laminates (FMLs) are novel materials employing stack-up configuration for alternate fibre-polymer plies and monolithic metallic sheets. These materials combine the superior mechanical properties of metals/alloys with lightweight, low thermal expansion of fibre-polymer composite layers. Synthetic fibre fabrics like aramid fibre, basalt fibre, carbon fibre, and glass fibre are commonly used in fibre metal laminates.  The effect of natural fibres as sandwiched plies in fibre metal laminates has been freshly explored in the current work. Banana fibre-epoxy layers have been combined with high strength, synthetic fabrics of aramid and ultra-high molecular weight polyethylene. Stacking sequences were developed with varied location of banana fibre-epoxy ply with AA6061 sheets as skins. The laminates were subjected to mechanical characterization comprising static tensile and flexural tests, followed by shock impact within a shock tube. There was a ~4-5% reduction in the tensile strength, ~37%-52% reduction in tensile modulus, ~5-23% reduction in the flexural strength, ~ 28-53% reduction in flexural modulus for the FMLs containing banana fibre-epoxy plies as compared to that without this ply. But, the FMLs with  banana fibre-epoxy plies showed enhanced shock impulse response as compared to the sequence without banana fibre-epoxy ply, with lower overall relative deformation (~14-21% lesser deformation).  

Effect of Natural Fibre-epoxy Plies on the Mechanical and Shock Wave Impact Response of Fibre Metal Laminates