AA6063 aluminium alloy is widely used for lightweight industrial applications due to its good corrosion resistance and weldability. Al6063 can be used to develop the metal foam with high strength and low weight material, majorly used in automotive, aerospace and defence sectors. Friction stir processing (FSP) is one of the promising techniques to fabricate metal foam among all metal processing methods. In current study AA6063 metal foam is fabricated by mixing of titanium hydride (TiH2) as a blowing agent and powdered alumina (Al2O3) as a stabilizing agent Process parameters are tool rotational speed, tool traversing speed, tool tilt angle, heat treatment temperature and heat treatment time which affects the mechanical characteristics such as density, porosity, compressive strength, and energy absorption capacity. An attempt has been made to optimize the effect of process parameters to attain better results using response surface methodology, in which a central composite half factorial design is used. An artificial neural network (ANN) in combination with the grey wolf optimization technique is used to validate the experimental results. The density of AA6063 is 2.7 g/cc, where, after foam fabrication density reduces up to 60%. The density of AA6063 foam varies from 0.98 to 1.56 g/cc, and a maximum porosity of 62.59% porosity has been achieved. SEM images confirm the presence of pores in the foam structure and reinforce particles in the porous structure.
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