| 摘要 |
PURPOSE:To annihilate defects by an HIP method and considerably improve the yields of products by beforehand expanding a cast material having large-size defects to about the sizes at which they are annihilated by hot hydrostatic pressing (HIP) treatment. CONSTITUTION:Of large-size casting defects 3, 4, 4', the part of a drawing cavity 3 is partly cut off as shown by a dotted line, and the part of the defect 4 is cut and pierced like a dotted line, and a fillter 5 of the same material as that of the cast material 1 is filled in the hole thus made. Thence, the material 1 is subjected to elongation such as rolling or casting, so that the gaps (d) of the cavities of the defect parts 3, 4, 4' are made sufficiently small to about the sizes at which the cavities are annihilated by HIP treatment. A strap 6 of the same material as that of the material 1 is abutted to the defect 3, and the circumferential part thereof is welded 7. Similar sealing treatment is applied to the defect 4 as well. Next, the material is subjected to HIP treatment in a high-temp. high-pressure gaseous atmosphere according to conventional methods, whereby the defects 3, 4, 4' are annihilated. |
