ELECTRON BEAM WELDING METHOD FOR LOW ALLOY STEELS

PURPOSE:To improve the toughness of weld metals by inserting a material which consists of specific chemical components and has the width larger than the width of a welding molten part into the groove between base metals and subjecting the boundaries between the respective base metals and the insert material to electron beam welding. CONSTITUTION:The insert material 2 which consists of such chemical components as to form the weld metal having sufficient toughness when subjected to nearly 50% dilution with the base metals 1, 1 consisting of low alloy or resembling component steels and has the width larger than the width of the weld zone formed by the electron beam welding is inserted into the groove 1a between the base metals 1, 1. The boundary between the one base metal 1 and the insert material 2 is subjected to the electron beam welding to form the weld metal 3 and the other base metal 1 is subjected to the same electron beam welding to form the weld metal 4. The dilution rate of the base metals and the insert material is increased in this way and the adjustment range of the compsn. of the weld metals is widened. The toughness thereof is thus improved.