| 摘要 |
PROBLEM TO BE SOLVED: To carry out the safe forming at a high temperature without changing a die by sealing both end parts of a tubular blank consisting of a deformable metal, heating the blank to the specified temperature of deformation, feeding the gas inside, and drawing/elongating the blank to be deformed. SOLUTION: A tubular blank 14 consisting of aluminum alloy or the like is arranged in a hydro-forming die 10 having a cavity 11 in a desired shape. The gas heated to the temperature exceeding 350 deg.C but lower than the melting point of the blank 14 is fed to the inside 16 of the blank 14 through a conduit 31 piercing a joining head 20 of a piston 19 from a source 30 under the specified pressure. A desired compression force is applied to both end parts in the axial direction of the blank 14 through pistons 18, 19. The blank 14 is drawn or elongated by the pressurized gas and the pistons 18 and 19, and deformed outwardly in the radial direction so as to be brought into contact with a surrounding wall of the die. |
