PURPOSE: To prevent the generation of a blow hole simultaneously with making the bead shape better by using the plasma arc of straight polarity as the heat source and by adding oxygen in a buildup welding as well in case of performing the buildup welding on the surface of a base metal by feeding a powder into the heat source.
CONSTITUTION: That which has ≤1.5 short and long ratio and is of a globular shape is used as the alloy powder to be used in the powder buildup welding. Since this powder has a good feedability, the inconvenience of a boiled water shortage or the ununiformity in bead width is not caused at the powder buildup welding time and the bead shape becomes better. The penetration of the buildup welding metal onto the base metal is increased as well because of the penetration of the molten powder for the base metal surface being bettered by using the plasma arc of straight polarity as the heat source. By adding oxygen further at buildup welding time the generation of a blow hole in the buildup welding metal can be prevented.
NAGATA MASA
HANASHIMA SHIGEO
Next Patent: NARROW GAP ARC WELDING METHOD FOR MAGNETIC MATERIAL