Effect of Relative Motion between Weld Tool and Work Piece on Microstructure of Ultrasonically Welded Joint

Abstract:

Ultrasonic welding is conducted using pure aluminum sheets to investigate effect of the transitional welding processes comprised of three transitional stages on the formation of the weld microstructure. In the first stage of ultrasonic welding, the relative motion mainly occurred between the workpieces, and a partially bonded region was observed in the weld interface. In the second stage, the relative motion at the weld interface was suppressed by the formation of the partially bonded region, while relative motion between the weld tool and the workpiece in contact with the weld tool. The relative motion at the weld tool/workpiece caused weld temperature rise with a penetration the weld tool edge. In the third stage, a plastic deformation zone generated by the relative motion at the weld tool/workpiece spread into the lower side of weld part as the welding time increased. It is proposed that the formation of weld microstructure in ultrasonic welding is attributed to the thermo-mechanically effect of the relative motion of the weld tool and workpiece.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 1782-1787
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.1782
• Online since: May 2014
• Authors: Tomohiro Sasaki, Yusuke Hosokawa
• Keywords: Digital Image Correlation Method, Joint Strength, Solid State Welding, Ultrasonic Welding, Welding Process

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