Characterization of AA6061-ZrO2-C friction stir welded composite joints

Abstract

In present work, investigation of metallurgical and mechanical characterization of Friction Stir Welded MMC material, theinfluence of micro structural properties on mechanical properties using different heat inputs were conducted. These heat inputgeneration depend on the FSW process parameters such as Tool Rotational Speed, Welding Speed and Axial Load. The FSWprocess parameters were set such as the tool rotational speed in the range of 800 to 1000 rpm, axial load in the range of 4 to6 kN and a constant welding speed 50 mm/min to fabricate the FS welded specimen of MMC materials. These processparameters play a major role in determining grain growth, phase transformation and change in microstructure of differentzones of weldment like welded nugget zone (WNZ), thermo- mechanically affected zone (TMAZ), heat affected zone (HAZ)and base metal (BM). Moreover, the effects of changes in the microstructure help in improvements of mechanical propertieslike tensile strength and hardness. The weld joints obtained with medium heat input produced the fine grains and maximumtensile strength of 198 MPa and hardness of 56 HRB at the tool rotational speed of 800 rpm, welding speed of 50 mm/minand axial load of 5 kN. The optical microscope (OM) and EDX analysis are employed to identify the presence of the matrix,reinforcement particulates in HMMCs and to confirm defect free welds attained at the WZ, TMAZ and HAZ during themedium heat input condition.