Investigation of microstructural and mechanical properties of Al alloy 7075-T6/B4C nanocomposite concocted via friction stir process

Magnanimously Aluminium metal matrix composites (MMCs) are acknowledged worldwide for keeping exceptional strength to weight ratio for which these are incorporated extensively in Aerospace and Automobile industries and gained potential limelight. Moreover, the material response outreach potential or the composite functionality potential are exclusively driven by tuning of the reinforcement materials. Herein, Al composites were concocted by introducing micro and nano Boron Carbide (B 4 C) powder into aluminium alloy AA 7075-T6 material matrix through Friction Stir Processing (FSP) with a motivation to enhance the mechanical and damping properties. Further the influence of physical structure alteration of reinforcement B 4 C from micro to nano dimension on the composites were validated through various characterizations. The microstructure of the composites was observed with optical microscope and Electron back scattered diffraction (EBSD) methods respectively. A significant grain refinement was observed with nano-reinforced composite by clinching average grain size reduced to 2.9 μm relative to base material grain size of 37 μm. The average hardness of nano-reinforced MMCs was found to be 66% higher than base material recorded a value of 141 HV. Furthermore, the AA7075-T6 composites were studied for their thermal and mechanical cyclic damping performance in the temperature range from ─ 60 to 60 °C and depicted exceptionally good damping property.