MICROSTRUCTURAL AND MECHANICAL CHARACTERIZATION OF FRICTION STIR WELD ON A AEROSPACE ALUMINIUM ALLOY

FSW is a solid state welding process and joining similar or dissimilar metals in which the relative motion between the tool and the work piece produces heat which makes the material of two edges being joined by plastic atomic diffusion.FSW widely used for the welding of light and difficult to weld metals and their alloys like aluminium, magnesium, copper etc. For FSW process tool is a critical component to the success of the process. FSW process used for the aerospace, railway, land transportation, ship building/marine, and the construction industries. For the experimentation of FSW high carbon high chromium (HCHCr) tool steel with tapered cylindrical pin shape having 50-55 HRC is used. It is having extremely high wear resistance properties, good softening resistance at elevated temperature, fine carbide size and grain size with high toughness and can withstands the impact load. All experiments are performed using AL 2014 aluminium alloy as a work piece. In this experimental work tool rotational speed (rpm), welding speed (mm/min) and axial tool tilt angle (degree) are used as process parameters. The main response variables were weld quality and weld strength.