The Influence of Shielding Gas Configurations on Formability of the Ferritic Stainless Steel Laser Weld

According to previous studies the careful argon shielding of the weld is very important in order to achieve a ductile and formable laser weld of Ti-stabilized ferritic stainless steel. In practice it is often difficult to use the root gas shielding of the laser weld. The aim of this study was to determine the sufficient practise of gas shielding in order to achieve the ductile laser weld. According to Erichsen formability results the shielding gas nozzle in the post weld side must be used in order to reach the good formability of the laser weld. The single shielding gas pipe before the weld is not a sufficient method for the gas shielding. There is no need to use root gas in order to achieve a ductile weld. The single shielding gas pipe before the weld can cause a uptake blast in the key hole and further oxidize the weld metal.