Interfacial Temperature Variation in Friction Stir Lap Welding of AA7075

Abstract:

Friction stir welding (FSW) is often preferred for joining aluminium and other lightweight metals in the square butt and lap configurations. The present work focuses on studying the interfacial temperature variation along and transverse to the weld direction during friction stir lap welding (FSLW) of AA7075-T6 mounting the thermocouples on both the advancing side (AS) and retreating side (RS) of the joint during FSLW of 3 mm thick plates using two different pin lengths. The peak temperature noted at the starting, middle, and end of the weld length is consistent, thus suggesting a steady heat generation during the process. However, there is an asymmetry in temperature distribution at the AS and RS of the joint, and the temperature recorded on AS is higher than RS. The peak temperature at a location reaches after a delay of the tool passes, suggesting a variation between the leading and trailing sides. The peak temperature for the joint obtained with the 4 mm pin length is around 40-50 °C higher than the joint with 3 mm pin length.

• Periodical: Key Engineering Materials (Volume 1012)
• Pages: 57-63
• DOI: https://doi.org/10.4028/p-CpFbt9
• Online since: May 2025
• Authors: Nikhil Kumar, Anirban Bhattacharya*
• Keywords: AA7075-T6, Asymmetry, Friction Stir Lap Welding, Interface Temperature, Pin Length

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