| 摘要 |
PURPOSE:To prevent high-temp. cracking, etc. during welding of a titled stainless steel by using an Mg-contg. wire and applying specific AC excitation current to an excitation coil provided to the tip of a welding torch thereby oscillating and stirring a molten metal and forming finer crystal grains. CONSTITUTION:AC excitation current of 1-20Hz is passed to an excitation coil 7 wound around a magnetic conductor 6 at the tip of a torch which is a tungsten electrode 5 in TIG welding, etc. of a stainless steel lining plate 2 on a carbon steel 1 which is a base material. A voltage is impressed from a welding power source 8 between the electrode 5 and the plate 2 and DC welding current 9 is passed and at the same time a wire 11 is fed to form a molten metal. The current 9 flows radially from the electrode 5 to the molten metal and the plate 2. The molten metal is oscillated and stirred clockwise or counterclockwise by the Lorentz force generated when the excitation current is applied. Finer crystal grains of the molten metal 3 are thus formed and the complete austentic stainless steel is welded without high temp. crack. |
