| 摘要 |
PURPOSE:To obtain specified rate of dilution over whole build up welding by changing peak current value of welding current to more than three grades and making the current value small in build up welding for a base metal. CONSTITUTION:An arc generated at the tip of an electrode 12 in a plasma arc torch 10 is made to a plasma arc by gas from a plasma gas supplying device 24. This plasma arc is shifted to between the torch 10 and the base metal 54 from inside of the torch 10 by welding current. At this time, peak current of welding current is changed to more than three grades, and at the same time, peak current value is made small and supplied with progress of building up. Powdery material supplied from a powder supplying device 36 is molten and carried to a weld zone 58 of the base metal 54 and specified building up is performed. |
