摘要 |
A single crystal turbine blade has a portion of its attachment section reinforced by a core containing a fine grained, polycrystalline alloy. The blade is prepared by casting a single crystal body with a cavity within the attachment section, and then filling the attachment section with the polycrystalline superalloy to form a composite structure. Filling is preferably accomplished by plasma spraying the cavity with the superalloy, and hot isostatically compacting the sprayed superalloy to minimize porosity. The composite structure is then heat treated to develop an optimized microstructure in the dual alloy attachment section. The resulting turbine blade has improved low cycle fatigue life of the composite attachment section.
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