Product Code: ICA10_P141

Correlation Between Computer-Based Simulation Model and Practice of High-Speed Laser Welding of Polycarbonate
Authors:
Heidi Piili, Lappeenranta University of Technology, Laser Processing Technology Research Group; Lappeenranta Finland
Lauri Taimisto, Lappeenranta University of Technology, Laser Processing Technology Research Group; Lappeenranta Finland
Tuomas Purtonen, Lappeenranta University of Technology, Laser Processing Technology Research Group; Lappeenranta Finland
Saara Ruotsalainen, VTT Technical Research Centre of Finland; Lappeenranta Finland
Petri Laakso, VTT Technical Research Centre of Finland; Lappeenranta Finland
Antti Salminen, Lappeenranta University of Technology, Laser Processing Technology Research Group; Lappeenranta Finland
Presented at ICALEO 2010

High speed quasi-simultaneous welding can be considered as a process which can create high quality welds with short welding times and a wide power range. The flexibility of the process makes it possible to create welds with complex shapes and sizes and it enables new design possibilities for polymer components.

In most of cases laser welding results in scientific articles are studied by performing weld tests and the welding result i.e. the weld quality is evaluated afterwards. With a suitable simulation program most of this stage could be avoided. This study presents a computer based software Flexi2D for simulation of polymer welding. The software calculates the weld dimensions according to material properties and welding parameters. By the input data, a visual image about the heat input is created, which helps to understand the welding process.
The welding tests were carried out on injection molded polycarbonate test pieces with a 100 W fiber laser.

A preliminary study was carried out by authors and it showed very good correlation between results of this simulation program and welding results when welding time of 0.2 seconds was used. In this study a further detailed series of simulations are carried out based on promising results of a preliminary study for larger number of scans and also to different welding times. The correlation between the model and practice is verified by welding tests.