Corrosion resistant nickel base superalloys containing manganese

Claim 2

A marine gas turbine blade consisting essentially of: a. 12-20% Cr; b. 3-14% of a refractory metal selected from the group consisting of Ta, Re, Cb, W and Mo and mixtures thereof: c. 4-10% of a material selected from the group consisting of Al, Ti, and mixtures thereof, with the Al level being less than about one-half of the Cr level; d. 5-20% Co; e. 0.2 to 0.6% Mn; f. up to 0.25% C, up to 0.3% B, up to 0.1% Zr, up to 2% Hf; g. balance nickel; said blade forming protective chrome rich surface oxides in service and being resistant to hot corrosion in the temperature range of about 1200°-1400° F. as a result of the manganese addition.

Claim 3

A blade as in claim 1 in which the ratio of Ti to Al exceeds 1.

Claim 4

A blade as in claim 1 in which the Mo content is less than half of the total refractory metal content (Ta+Cb+Re+W+Mo).

Claim 5

A blade as in claim 1 in which the Mo content is less than 2%.

Claim 6

A blade as in claim 1 which is intended for use in single crystal form to which no intentional additions of C, B and Zr have been made.

Claim 7

A blade as in claim 1 which also displays enhanced creep resistance at 1650° F. as a result of the presence of manganese.

Claim 8

A gas turbine component comprised of: a. 12-20% Cr; b. 3-14% of a refractory metal selected from the group consisting of Ta, Cb, Re, W, and Mo and mixtures thereof; c. 4-10% of a material selected from the group consisting of Al, Ti and mixtures thereof, with the Al level being less than about one-half of the Cr level; d. 5-29% Co; e. 0.2 to 0.6% Mn; f. up to 0.25% C, up to 0.3% B, up to 0.1% Zr, up to 2% Hf; g. balance nickel; in which the ratio of Ti:Al exceeds 1, the Mo content is less than one-half of the total refractory metal content (Ta+Cb+Re+W+Mo), and the Mo content is less than 2%, said component forming protective chrome rich surface oxides in service and being resistant to hot corrosion in the temperature range of about 1200°-1400° F. as a result of the manganese addition.

Claim 9

A gas turbine component comprised of: a. 12-20% Cr; b. 3-14% of a refractory metal selected from the group consisting of Ta, Cb, Re, W, and Mo and mixtures thereof; c. 4-10% of a material selected from the group consisting of Al, Ti and mixtures thereof, with the Al level being less than about one-half of the Cr level; d. 5-29% Co; e. 0.2 to 0.6% Mn; f. up to 0.25% C, up to 0.3% B, up to 0.1% Zr, up to 2% Hf; g. balance nickel; in which the ratio of Ti:Al exceeds 1, the Mo content is less than one-half of the total refractory metal content (Ta+Cb+Re+W+Mo), and the Mo content is less than 2%, said component forming protective chrome rich surface oxides in service and being resistant to hot corrosion in the temperature range of about 1200°-1400° F. as a result of the manganese addition.