Enhancement of weld qualities in friction stir welding

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
The present research work started with the objective to deliver methodologies for the enhancement of joint properties in friction stir welding (FSW) process for similar and dissimilar materials as well as materials with different thickness. The role of process parameters in joining Mg alloy with FSW process is explored with emphasis on enhancement of mechanical properties of the joints. Taguchi grey relational analysis is implemented for investigating the influence of individual process parameters as well as interaction effects among parameters. Shoulder diameter is found to be the most influencing parameter for controlling the weld qualities followed by welding speed. The examination leads to the impression that defect free joints with sound mechanical and desirable microstructural properties can be achieved with low tool rotational speed, welding speed, plunging depth and high shoulder diameter. The investigation is carried a step forward towards the improvisation of weld qualities by inserting Al or Zn foil alloying elements at the faying edge of the joints. These alloying elements are selected based on the reaction feasibility with Mg. The investigation is supported with phase analysis and macromicrostructural analysis which confirms Zn as to be the most advisable alloying element for enhancement of mechanical properties of AM20 Mg joints.
Supervisor: Sukhomay Pal