| 摘要 |
Method of manufacturing a workpiece of any given cross-sectional dimensions from an oxide-dispersion-hardened nickel-based superalloy available in the form of coarse-grained longitudinally directed columnar crystals by connecting previously very finely machined workpiece parts derived from a semi-finished product by diffusion-bonding using hot isostatic pressing, the workpiece parts being first heat-treated under a protective gas in the temperature range of 50 DEG to 100 DEG C. below the recrystallization temperature, under a pressure pk of not more than 5 MPa with the machined surfaces to be connected joined together, the workpiece then being heated at least to a critical temperature TK, above which no further cold working takes place, and the pressure then being gradually increased to the diffusion bonding pressure pmax of 100 to 300 MPa with simultaneous increase in temperature are a heating rate of not more of 2 DEG C./min to the diffusion bonding temperature TD of 0 to 50 DEG C. below the recrystallization temperature, this condition being maintained for 1 to 24 hours. Safe variant: only raise the pressure when TD has been reached!Application: gas turbine blading of large dimensions.
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