In this experimental research work, the metal matrix composites of A356 alloy were prepared by reinforcing different shaped particles Aluminium Nitride (AlN), Multi-Walled Carbon Nano Tube (MWCNT) and graphite (Gr). The main objective of this research work was to investigate the influence of different shaped reinforcement in the microstructure and mechanical behaviour of composites. The reinforcements (AlN & MWCNT) were added as 0.5, 0.75, 1 and 2 vol% and the graphite was maintained in 0.5 vol%. The composites were fabricated using stir casting followed by ultrasonic vibration treatment. The tensile, compression and Brinell hardness test were carried out by following ASTM standards. The characterization of reinforcements, castings and fractured surfaces was performed using Optical Microscope (OM) and Scanning Electron Microscope (SEM). The mechanical tests and characterization results revealed that there was a significant influence of morphology of reinforcements on mechanical properties of the materials. Particle strengthening and grain refinement strengthening were found to be operative in the composites. The SEM micrograph of fractured surface of composites with MWCNT exhibited the crack bridging effect as strengthening mechanism apart from particle strengthening. The porosity and cluster of reinforcements were observed in the composites with MWCNT more than 1 vol% of and AlN 0.75 vol%.

This research work is focused on development of epoxy based fiber metal laminate (FML) that comprised of multi-walled carbon nano-tube (MWCNT), glass fiber, and aluminum metal sheet. The hand layup technique was employed to fabricate the sandwich FML with different weight percentages (3, 4, and 5 wt%.) of MWCNT. The mechanical properties of the developed FMLs were determined through tensile, flexural, lap shear, and hardness tests following ASTM and IS standards. The scanning electron microscope (SEM) was used to characterize the failure mechanism of composites. The FML with MWCNT offered superior tensile and shear properties up to the addition of 4 wt%. The MWCNTs were found to be agglomerated in the epoxy when added more than 4 wt%. The FML's showed larger deformation before complete failure in shear mode with respect to the addition of MWCNTs. However, there was no considerable improvement recorded in the flexural and impact behavior of the FML composition. The addition of MWCNT fillers in the epoxy turned it more brittle and exhibited comparatively less deformation before failure in flexural mode.

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