Product Code: ICAL08_602

The Effect of Clamping Force when using Ultrasonic Welding Ridge on Ultra High Speed Fiber Laser Welding of Polycarbonate
Authors:
Tuomas Purtonen, Lappeenranta University of Technology; Lappeenranta Finland
Antti Salminen, Lappeenranta University of Technology; Lappeenranta Finland
Petri Laakso, VTT Technical Research Centre of Finland; Lappeenranta Finland
Presented at ICALEO 2008

The electronic and automobile industries are having a growing interest in laser welding of polymers. Laser welding of polycarbonate has been widely researched in numerous different occasions. Novel ways for creating stronger and visually better welds are continuously studied. The need for short welding times and narrow welds gives a challenge for quasi-simultaneous laser welding: The welds have to be as strong as the base material when weld widths are from 0.2 mm and up and welding times under 1 second. This paper examines the effect of clamping force during welding and the possibilities to use an ultrasonic ridge on top of the absorbing part to improve the weld properties. Depending on the welded part there is a need for high clamping forces in order to close all air gaps due to some variation on injection moulded parts. Results on weld widths on different clamping forces with and without the ridge are presented. Outcome of the research is discussed based on these results.