Application of Laser Beam Welding to Thin Steel Sheet

Abstract

As Laser beam can be focused to pointed area, it is suitable to apply high speed welding of thin sheet metal. This experiment was carried out to know what advantage can be expected by applying Laser beam welding to surface coated steel sheet and austenitic stainless steel.The results obtained in this report are as follows;1) Steel sheet can be welded with much smaller distortion by Laser beam welding, compared with TIG welding. For coated sheet, Laser beam welding gives less damage to coated layer than that of TIG weld-ing. It is possible to make full penetration weld to use 3-5 times faster speed by Laser beam welding than by TIG welding.2) TIG weld metal of Zn coated sheet shows Zn rich region at surface but Laser weld metal does not.3) Laser beam welded joints of stainless steel show little weld decay tendency, which is almost same level as electron beam welded joint.