Within the last years laser beam welding has been extended to welding of micro parts. The trend of miniaturization is still ongoing and strengthened this development. This contribution will give an overview of the new application of laser beam welding in watch industry and electronics industry. The combination of dissimilar materials like brass and stainless steel is often needed in watch movements due to tribologic aspects. Here laser beam micro welding offers an alternative to conventional joining techniques like press fit. Since watch components are very small the locally limited heat input of the laser beam offers the possibility of decreasing the weld seam width below 200 μm. The use of shielding gas prevents from oxidation of the surface. Using the pulse forming capability of a pulsed Nd:YAG laser source the depth and the width of the weld seam as well as the surface quality can be influenced. Several watch components could be joined by means of laser beam micro welding. The width of the seam could be reduced to 100-200μm. The joining geometries of an axis/wheel combination are in the range of 100μm to 1mm diameter of the axis and about 200μm wheel thickness. The work to be presented has been funded by the European Commission in a project under the contract BRPR-CT-0634.
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