Effects of Workpiece Size on Temperature Distribution During FSW of AZ31 Magnesium Alloy

Abstract:

This study aims to experimentally explore the effects of varying workpiece sizes on thermal histories and temperature distributions during FSW processes of AZ31 magnesium alloy. Similar layouts of thermocouples were designed to measure thermal histories of feature points at different locations along the welding direction. A tendency of peak temperature presented that it kept climbing gradually for a distance about 60mm, then approached to change smoothly. A time hysteresis has been also found that the time of the measured temperature reaching the peak lagged behind the time of the tool staying or arriving at these feature points. The longest hysteretic time was about 6s, as the welding process proceeded, it shortened slowly. The longer the length of the welding direction was, the more obvious the tendency was, but the hysteresis, on the contrary. The intense impact of the heat accumulation was embodied in terms of the time staying above the recrystallization temperature. According to these results, it is inferred that the welding process reaches a real stable stage after the tool traversed a 60mm’s distance.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 734-741
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.734
• Online since: March 2016
• Authors: Sheng Lu, Xing Yin Zhu, Bin Liu, Yun Peng Wang
• Keywords: FSW, Magnesium Alloy, Size Effects, Temperature Distribution

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