| 摘要 |
<p>A rapidly solidified foil for a ring-like welding material is formed by spraying a molten metal on the side of a roll rotating at a high speed and rapidly solidifying the same, and the ring-like foil is formed into a coil. It has also a fold portion concentric with the rings. A nozzle opening surface is opposed to the roll side vertical or inclined to the axis of rotation, the opening is slit-like, the longitudinal direction of the opening is parallel to a radial direction of the roll side, the molten metal is sprayed, and the rapidly solidified foil is peeled. When pipes such as steel pipes are butt-welded with the pipe end surfaces vertical to the axis of the pipe, the rapidly solidified foil is placed between the pipe end surfaces. The rapidly solidified foil is produced with high yield and high working factor. Because the thickness in the width direction of the ring foil is made uniform or the surface area of the welding material is increased, the welding accuracy and welding strength are improved.</p> |
