| 摘要 |
The present invention relates to a process for manufacturing at least one single-crystal seed that can be used as a starter seed in the manufacture of a single-crystal high-pressure turbine nozzle, with at least one vane between two platforms, by metal casting, wherein: a wax pattern is produced which comprises: a first element forming the pattern for the nozzle, a second element forming the pattern for the starter seed, including a flat face for localizing the crystalline orientations, and at least a third element incorporating a pattern for the crude seed with a flat face for localizing the crystalline orientations; a ceramic shell mold is formed from said wax pattern and a starter seed, including said flat face for localizing the crystalline orientations, is incorporated into the mold; a metal is poured into the mold; the metal undergoes directional solidification in the mold from the starter seed, so that the crude seed obtained has the same crystallographic structure as the part; and the crude seed obtained is separated from the part for subsequent use as a starter seed.
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