| 摘要 |
PURPOSE:To obtain a product having a high sealing effect in the juncture and having high joint strength, by disposing a brazing material annularly near the outside circumference of a blank material. CONSTITUTION:A brazing material 5 subjected to pipe working is fitted on the outside circumference of a central blank material 4 in tight contact therewith, and is subjected repeatedly to heat treatments and drawing, whereby a primary composite material 6 of a prescribed size is obtd. A hole of the diameter equal to the outside diameter of the material 6 is opened in the same blank material as the material 6 to make a sheath material 7, and the material 6 is inserted and fitted into the hole of the material 7. Both materials are subjected repeatedly to heat treatments and drawing, whereby the blank material as a composite material is completed. |
