Product Code: ICAL08_603

Effects of the Diode Laser Irradiation on Polypropylene due toTransmission Welding
Authors:
Elhem Ghorbel, Universite De Cergy Pontoise; Cergy Pontoise France
Giuseppe Casalino, DIMeG - Politecnico di Bari; Bari Italy
Stephane Abed, Cooperation Laser Franco-Allemande; Arceuil Cedex France
Presented at ICALEO 2008

Diode laser welding is a non-contact process especially efficient for joining thermoplastic polymers. This technology has already industrial applications in series production in some sectors like automobile and packaging but a lack of knowledge concerning the influence of thermal history on the weld seam morphology of semicrystalline polymer has to recover since it strongly influences the strength of the weld. The majority of the basic research concerns with the weld strength depending on polymer nature, optical properties, design and process parameters. This study focuses on the effects of welding the polypropylene with diode laser using the overlap joint configuration. The goal is to show the influence the laser power and the welding speed, on the geometry the microstructure and the hardness of the weld and thermal affected zones. Microscopic Fourier Transform Infrared (FTIR) Spectroscopy method was used to measure the variation of the cristallinity rate inside the weld seam. Also the influence of the carbon content in the polypropylene and the laser irradiation time were studied.