Patent ID: 7779889

Claim:
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, comprising: producing a wax pattern, the wax pattern comprising: a first element forming a pattern for the nozzle, a second element forming a pattern for the starter seed, including a flat face for localizing crystalline orientations, and at least a third element incorporating a pattern for a crude seed with a flat face for localizing the crystalline orientations, wherein the wax pattern is produced by injection molding in a first mold with wax so as to provide the first and second elements, separately producing the third element comprising a crude seed pattern by injection molding in a second mold with wax, and attaching the second mold to the first mold; forming a ceramic shell mold from said wax pattern; incorporating the starter seed into the mold, the starter seed including said flat face for localizing the crystalline orientations; pouring a metal into the mold; directionally solidifying the metal in the mold from the starter seed, so that the crude seed obtained has the same crystallographic structure as the nozzle; and separating the obtained crude seed from the nozzle for subsequent use as a starter seed.