Investigation of Vibration Assisted Friction Stir Welding and Comparison with Conventional Friction Stir Welding

Friction Stir Welding (FSW) applications in high strength alloys, such as stainless steel remain limited due to large axial welding force and consequent tool wear. It has been shown that applying the ultrasonic vibration on some processes such as turning and drilling the resultant forces are decreased and process condition is improved. In this paper the influence of applying vibration on FSW was investigated using Simulink and Matlab programming tools. The resultant axial force of conventional FSW and Vibration Assisted FSW (VAFSW) were compared in frequency and time domain state spaces. A good correlation between FSW simulation and experiments was observed. For further investigation of VAFSW the response surface of design of experiment (DOE) method was used. The simulation results indicated that the vibration helps to decrease the axial welding force. Using DOE method the influence of implemented frequency and vibration speed amplitude in FSW was found. Force reduction of 6 to 17% by applying the vibration during the friction stir welding was observed.

Keywords:

Vibration assisted , Friction stir welding , Force analysis , Design of experiments