Optimization of control factors on mechanical properties of friction stir processed AZ91B/Al2O3 nanocomposites

Magnesium (Mg) alloys are used in the automotive, aerospace, and shipbuilding industries to decrease their component weight and increase fuel economy. Friction Stir Processing (FSP) technology was utilized to reinforce Alumina (Al2O3) nanoparticles of 30 nm onto the surface of Mg alloys to improve the alloy's mechanical characteristics. Using the Response Surface Method (RSM) with L16-based trials, an effort was made to optimize responses such as Ultimate Tensile Strength (UTS), Elongation Percentage (%E), and Microhardness (MH) in the weld zone of FSPed Composite Joints with regard to their input factors. The variable groove size was found to be the most important element determining weld quality, followed by tool rotation and travel speed. Metallurgical investigation revealed a consistent dispersion of nanoparticles in the Stir Zone, as well as a defined interface between the nanoparticles and matrix and no indication of intermetallic production. When base metal welded joints without reinforcement were compared to FSPed joints, the UTS,%E, and MH values showed the greatest improvements.