Conventional joining techniques like press fitting or crimping require the application of mechanical forces to the parts which, in combination with the tolerances of both parts to be joined, lead to imprecision and poor tensile strength. In contrast, laser beam micro welding provides consistent joining and high flexibility and it acts as an alternative as long as press fitting, crimping, screwing or gluing are not capable of batch production. Different parts and even different metals can be joined in a non-contact process at feed rates of up to 60 m/min and with weld seam lengths from 0.6 mm to 15.7 mm. Due to the low energy input, typically 1 J to 6 J, a weld width as small as 50 μm and a weld depth as small as 20 μm have been attained. This results in low distortion of the joined watch components. Since the first applications of laser beam micro welding of watch components showed promising results, the process has further been enhanced using the SHADOW technique. Aspects of the technique such as tensile strength, geometry and precision of the weld seam as well as the acceptance amongst the -mostly conservative- watch manufacturers have been improved.

Date Published: 17 October 2003
PDF: 12 pages
Proc. SPIE 4977, Photon Processing in Microelectronics and Photonics II, (17 October 2003); doi: 10.1117/12.482627

Published in SPIE Proceedings Vol. 4977:
Photon Processing in Microelectronics and Photonics II
Alberto Piqué; David B. Geohegan; Friedrich G. Bachmann; Koji Sugioka; Frank Träger; Jan J. Dubowski; Peter R. Herman; Willem Hoving; Kouichi Murakami; Kunihiko Washio; Jim Fieret, Editor(s)