Corrosion and oxidation resistant directionally solidified superalloy

Abstract

A nickel-based superalloy having a good balance between corrosion and oxidation resistance. The alloy provides good mechanical properties. The superalloy is suited for directional solidification casting but can also be used for conventional or single crystal casting techniques. The superalloy is well suited for the hot section components such as blades, vanes and ring segments for gas turbine engines. The superalloys can be used with various thermal barrier coatings

1 . A nickel-based superalloy expressed in weight percentages consisting essentially of:
 9.5 to 14.0 Cr;   7.0 to 11.0 Co;   1.0 to 2.5 Mo;   3.0 to 6.0 W;   1.0 to 6.0 Ta;   3.0 to 4.0 Al;   3.0 to 5.0 Ti;   0 to 1.0 Nb;   0.05 to 0.2 Hf;   0.05 to 0.2 Si;   0.005 to 0.02 B;   0 to 0.1 Zr;   0.05 to 0.15 C;   0.001 to 0.1 of a mixture of two or more rare earth metals selected from the group of consisting of Y, La, Ce, Nb, Dy, Pr, Sm, and Gd; and   balance formed from Ni.   
     
     
         2 . The superalloy of  claim 1 , wherein the superalloy consisting essentially of:
 11.6 to 12.7 Cr;   8.5 to 9.5 Co;   1.65 to 2.15 Mo;   3.0 to 4.1 W;   4.8 to 5.2 Ta;   3.4 to 3.8 A1;   3.9 to 4.25 Ti;   0 to 0.5 Nb;   0.1 to 0.15 Hf;   0.1 to 0.15 Si;   0.005 to 0.015 B;   0 to 0.02 Zr;   0.05 to 0.11 C;   0.01 to 0.05 of a mixture of two or more rare earth metals selected from the group of consisting of Y, La, Ce, Nb, Dy, Pr, Sm, and Gd; and   the balance formed from Ni.   
     
     
         3 . The superalloy of  claim 1 , wherein the superalloy consisting essentially of:
 12.2 Cr;   9.0 Co;   1.9 Mo;   3.8 W;   5.0 Ta;   3.6 Al;   4.1 Ti;   <0.2 Nb;   0.12 Hf;   0.12 Si;   0.01 B;   0.0075 Zr;   0.09 C;   0.02 of a mixture of two or more rare earth metals selected from the group consisting of Y, La, Ce, Nb, Dy, Pr, Sm, and Gd; and   the balance formed from Ni.