Nickel base gamma prime strengthened superalloy

Abstract

A nickel base gamma prime strengthened superalloy with a unique blend of high hot corrosion resistance, high oxidation resistance, high coating compatibility, good weldability, high phase stability and at least moderate creep resistance is disclosed. The composite includes: Up to 20 wt % Co, between 17 and 21 wt % Cr, between 2 and 5 wt % of Mo+W+Re, at most 2 wt % Mo, between 4 and 4.7 wt % AL, between 3 and 7 wt % Ta, 0.01 and 0.2 wt % Ta, between 0.01 and 0.3 wt % of C+Zr+B between 0.05 and 1 wt % Hf, between 0.05 and 1 wt % Si, and between 0.01 and 0.2 wt % of the sum of rare earths such as SC, Y, the actinides and the lanthanides. The composition is intended for use as base alloy for moderately stressed hot components and as filler alloy for cladding and weld repair in moderately stressed parts of hot components.

1 .- 17 . (canceled) 
     
     
         18 . A nickel base gamma prime strengthened superalloy comprising (in a wt. %):
 between 2 and 12 wt % Co;   between 17 and 21 wt % Cr;   between 2 and 5 wt % of Mo and/or W and/or Re;   up to 1 wt % Mo;   between 1 and 4 wt % W;   between 4 and 4.7 wt % Al;   between 3 and 7 wt % Ta;   between 0.01 and 0.3 wt % of C and/or Zr and/or B;   between 0.01 and 0.1 wt % of C;   between 0.01 and 0.15 wt % Zr;   between 0.002 and 0.02 wt % B;   between 0.05 and 1 wt % Hf;   between 0.05 and 1 wt % Si;   between 0.01 and 0.2 wt % of the sum of rare earths;   between 0.01 and 0.2 wt % of Ce and/or La and/or Y and/or Dy; and   balance Ni.   
     
     
         19 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , wherein the rare earth element(s) in the superalloy are at least one of the elements Sc, Y, actinides or lanthanides. 
     
     
         20 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , comprising:
 between 3 and 7 wt % Co;   between 17 and 19 wt % Cr;   between 0.5 and 1 wt % Mo;   between 2 and 3 wt % W;   between 4.2 and 4.6 wt % Al;   between 3.5 and 5 wt % Ta;   between 0.01 and 0.07 wt % C;   between 0.01 and 0.1 wt % Zr;   between 0.002 and 0.01 wt % B;   between 0.05 and 0.5 wt % Hf;   between 0.05 and 0.5 wt % Si; and   between 0.01 and 0.1 wt % of the sum of Ce+La+Y+Dy.   
     
     
         21 . The nickel base gamma prime strengthened superalloy as claimed in  claim 20 , comprising:
 between 4.5 and 5.5 wt % Co;   between 17.7 and 18.3 wt % Cr;   between 0.7 and 0.9 wt % Mo;   between 2.3 and 2.7 wt % W;   between 4.3 and 4.5 wt % Al;   between 4.2 and 4.6 wt % Ta;   between 0.02 and 0.04 wt % C;   between 0.02 and 0.05 wt % Zr;   between 0.002 and 0.008 wt % B;   between 0.07 and 0.13 wt % Hf;   between 0.07 and 0.13 wt % Si; and   between 0.01 and 0.03 wt % of the sum of Ce+La+Y+Dy.   
     
     
         22 . The nickel base gamma prime strengthened superalloy as claimed in  claim 21 , comprising:
 essentially 5 wt % Co;   essentially 18 wt % Cr;   essentially 0.8 wt % Mo;   essentially 2.5 wt % W;   essentially 4.4 wt % Al;   essentially 4.4 wt % Ta;   essentially 0.03 wt % C;   essentially 0.03 wt % Zr;   essentially 0.005 wt % B;   essentially 0.1 wt % Hf;   essentially 0.1 wt % Si; and   essentially 0.02 wt % Ce.   
     
     
         23 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , comprising:
 between 3 and 7 wt % Co;   between 19 and 21 wt % Cr;   between 2 and 4 wt % W;   between 4.3 and 4.7 wt % Al;   between 4 and 7 wt % Ta;   between 0.01 and 0.07 wt % C;   between 0.01 and 0.1 wt % Zr;   between 0.002 and 0.01 wt % B;   between 0.05 and 0.5 wt % Hf;   between 0.05 and 0.5 wt % Si; and   between 0.01 and 0.1 wt % of the sum of Ce+La+Y+Dy.   
     
     
         24 . The nickel base gamma prime strengthened superalloy as claimed in  claim 23 , comprising:
 between 4.5 and 5.5 wt % Co;   between 19.7 and 20.3 wt % Cr;   between 2.7 and 3.3 wt % W;   between 4.4 and 4.6 wt % Al;   between 5.3 and 5.7 wt % Ta;   between 0.02 and 0.04 wt % C;   between 0.02 and 0.05 wt % Zr;   between 0.002 and 0.008 wt % B;   between 0.07 and 0.13 wt % Hf;   between 0.07 and 0.13 wt % Si; and   between 0.01 and 0.03 wt % of the sum of Ce+La+Y+Dy.   
     
     
         25 . A nickel base gamma prime strengthened superalloy as claimed in  claim 24  comprising:
 essentially 5 wt % Co; 
 essentially 20 wt % Cr; 
 essentially 3 wt % W; 
 essentially 4.5 wt % Al; 
 essentially 5.5 wt % Ta; 
 essentially 0.03 wt % C; 
 essentially 0.03 wt % Zr; 
 essentially 0.005 wt % B; 
 essentially 0.1 wt % Hf; 
 essentially 0.1 wt % Si; and 
 essentially 0.02 wt % Ce. 
 
     
     
         26 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , wherein the superalloy is processed using a clean production process resulting in less than 2 ppmw S. 
     
     
         27 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 ,
 wherein the superalloy is a hot component of a machine.   
     
     
         28 . The nickel base gamma prime strengthened superalloy as claimed in  claim 27 , wherein the hot component is a gas turbine component such as a vane, a heat shield, a sealing or a combustor part. 
     
     
         29 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 ,
 wherein the superalloy is a filler alloy for cladding or repair welding in moderately stressed areas of hot components.   
     
     
         30 . The nickel base gamma prime strengthened superalloy as claimed in  claim 29 , wherein the hot component is a gas turbine component. 
     
     
         31 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , wherein the superalloy is in monocrystalline form. 
     
     
         32 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , wherein the superalloy is in directionally solidified form. 
     
     
         33 . The nickel base gamma prime strengthened superalloy as claimed in  claim 18 , wherein the superalloy is in equiaxed form.