Product Code: ICAL05_P567

Development of an Advanced Dual Beam Head for Laser Lap Joining of Zinc Coated Steel Sheet
Authors:
Mariana Forrest, DaimlerChrysler Corporation; Troy MI USA
Feng Lu, Feng Lu Consulting; Bloomfield Hills MI USA
Presented at ICALEO 2005

Laser welding has shown a lot of advantages over the currently widely used resistance spot welding for automobile assembly application. These include cost savings (due to increased production speed, reduced assembly line length, etc.) and performance improvement (increased stiffness, less heat affected zone width and distortion etc). The only major problem that prevents the application of laser welding to mass production application is the zinc expulsion at the sheet/sheet interface if no gap is provided between the two sheets to be lap joined. After years of research, a practical solution is finally obtained (as reported in ICALEO 2004). This paper describes the development of a new laser welding head for implementing in production this new solution. After a brief review of the history of all major research works in this field, the fundamental principles that this head is based upon are discussed. Then the design parameters and the final manufactured head characteristics are illustrated. The head calibration procedure and equipment used for this purpose are also discussed. Finally, results from preliminary welding trials using this newly fabricated head are presented.