| 摘要 |
PURPOSE:To permit forming of a metallic material having excellent high-temp. strength without using a high-temp. isostatic press or extrusion by packing powder of a high-strength hard-to-work material with a material having specific strength, heating the material to a superplasticity developing temp. and forging the same by using a low-temp. die. CONSTITUTION:The powder material of the high-strength hard-to-work material which can develop superplasticity is packed with the material having the strength of >=1/2 the superplasticity developing strength of the sintered preform material of said powder at the superplasticity developing temp. of said preform material. The thickness of the packing material is preferably >=1/5 the diameter of the product. After such material is heated to and held at the superplasticity developing temp., the material is forged by using the die of a relatively low temp., for example, the die which is kept heated at the heat resisting temp. or below in an about 200-950 deg.C range. An isostatic effect better than in constant-temp. forging is obtd. by cooling of the pack material by such die. Production of a large-sized turbine disk, etc., is permitted by this method.
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