Session: MF-01-02 Application of Fracture Mechanics in Failure Assessment II

Paper Number: 62249

Start Time: Thursday, July 15, 2021, 09:00 AM

62249 - Vibration-Assisted Friction Stir Welding of AA 2024-T3 Plates 

In this research, the weldability of AA 2024 plates using vibration-assisted friction stir welding (VaFSW) is primarily inspected. The vibration imparted to the fixture holding the specimens in VaFSW differentiates this state-of-art process from the conventional friction stir welding (FSW) technique. For the large scale welding applications, it is ideal to vibrate the tool with required amplitude and frequency for the optimum performance. Due to limitation in applying vibration to the tool in a milling machine, the vibration is imparted to a custom-designed fixture and rig setup.  Fixture, which holds the plates rigidly, is mechanically shaken during the friction stir welding process to boost the material strain in the weld region. The VaFSW is performed with 1800 rpm tool rotational speed, 18 mm/min travel speed and at four intermittent levels of vibrational frequencies (10.11 Hz, 13.56 Hz, 16.67 Hz, 25.17 Hz). A detailed welding morphology and mechanical characteristics are inspected and compared with all combinations of parameters. Finally, the results of VaFSW are compared with conventional FSW. When VaFSW is compared to the conventional FSW, the tensile strength is enhanced and hardness is increased in each of the zones – Nugget zone, heat affected zone, and base metal. Results of the traction experiment indicated that the VaFSW-ed specimens exhibited higher strength and brittleness than those of FSW-ed specimens. This is due to excessive plasticized material during VaFSW resulting in greater grain dislocation. Moreover, the mechanical characteristics of weld joints enhanced with the increase in the vibrational frequency. This study was promising for verifying the capability of VaFSW over FSW for producing quality weld joints.

Presenting Author: Dinu Thomas Thekkuden United Arab Emirates University

Authors:

Ibrahim Sabry Modern Academy for Engineering and Technology
Abdel-Hamid Ismail Mourad United Arab Emirates University
Dinu Thomas Thekkuden United Arab Emirates University