| 摘要 |
PURPOSE:To supply stably a plasma arc and to obtain an excellent bead shape by converting to a square and a constant-voltage a current-voltage characteristic of a welding current for shifting the plasma arc toward a working member from the inside of a torch. CONSTITUTION:A plasma gas is supplied to a plasma arc torch 10 from a plasma gas supplying device 24, and an arc generated in the tip of an electrode 12 in the torch 10 to be a plasma arc. Subsequently, a current-voltage characteristic of a power source 50 is converted to a square, and a welding current converted to a constant-voltage in a working current range is made to flow between the torch 10 and a working member 54. Next, said plasma arc is shifted to between the torck 10 and the member 54 from the torch 10. At the same time, a powder material is supplied into the plasma arc, melted and shifted to the surface of the member 54, and padded. |
