PURPOSE: To obtain a reverse partitioning Ni-base superalloy single crystal product having high strength at high temp. in which formation of TCP phase can be decreased after the product is exposed to a high temp. environment by specifying the compsn. containing Re, Mo, Cr, Cb, Al, Ti, W, Ru, Ta or the like.
CONSTITUTION: This reverse partitioning Ni-base superalloy single crystal product contains, by atomic %, 1.3 to 3% Re; 2.0 to 3.7% Ta; 4.0 to 18.0% Co; 0 to 0.2% Hf; 0 to 0.3% C; 0 to 0.05% B; 0 to 0.03% Y; 0 to 2.0% Mo, 1.5 to 7.2% Cr; 0 to 0.7% Cb; 12.0 to 15.0% Al; 0 to 1.3% Ti; 1.0 to 2.5% W; 0.25 to 4.0% Ru; and the balance Ni and incidental impurities. The product has a γ phase and a γ' phase. In this alloy, Ru is substantially substituted for Al and Cr in the γ' phase while partitions these elements in the γ phase. Moreover, W, Cr and Re are partitioned in the γ' phase in the presence of Ru. Thereby, the obtd. product has excellent stress rupture life and microstructural stability, in which formation of TCP phase harmful at high temp. can be suppressed.
UIRIAMU SUKOTSUTO WARUSUTON
AARU UOOREN ROSU
RAMUGOPARU DARORIA
