Nickel base superalloy with multiple reactive elements and use of said superalloy in complex material systems

Abstract

A nickel-base y/y′ superalloy with a blend of at most moderate cost, high oxidation resistance, high hot corrosion resistance, moderate strengthening, adequate allow stability and comparatively good weldability is provided. The alloy includes up to 20 wt % of the sum of Co and Fe, between 17 and 21 wt % Cr, between 0.5 and 3 wt % of the sum of Mo and W, at most 2 wt % Mo, between 4.8 and 6 wt % Al, between 1.5 and 5 wt % Ta, between 0.01 and 0.2 wt % of the sum of C and B, between 0.01 and 0.2 wt % Zr between 0.05 and 1.5 wt % Hf, between 0.05 and 1.0 wtz % Si, and between 0.01 and 0.5 wt % of the sum of rare earths such as Sc, Y, the actinides and the lanthanides, such that at least two of these rare earths are present in the alloy, and no more than 0.3 wt % of any of these rare earths.

1 - 23 . (canceled) 
     
     
         24 . A nickel base γ/γ′ superalloy, comprising:
 up to 20 wt % of a first sum of Co and Fe; 
 between 17 and 21 wt % Cr; 
 between 0.5 and 3 wt % of a second sum of Mo and W; 
 at most 2 wt % Mo; 
 between 4.8 and 6 wt % Al; 
 between 1.5 and 5 wt % Ta; 
 between 0.01 and 0.2 wt % of a third sum of C and B; 
 between 0.01 and 0.2 wt % Zr; 
 between 0.05 and 1.5 wt % Hf; 
 between 0.05 and 1.0 wt % Si; and 
 between 0.01 and 0.5 wt % of a fourth sum of rare earths of which at least two are present in the alloy, and at most 0.3 wt % of any rare earth. 
 
     
     
         25 . A nickel base γ/γ′ superalloy consisting of:
 up to 20 wt % of a first sum of Co and Fe; 
 between 17 and 21 wt % Cr; 
 between 0.5 and 3 wt % of a second sum of Mo and W; 
 at most 2 wt % Mo; 
 between 4.8 and 6 wt % Al; 
 between 1.5 and 5 wt % Ta; 
 between 0.01 and 0.2 wt % of a third sum of C and B; 
 between 0.01 and 0.2 wt % Zr; 
 between 0.05 and 1.5 wt % Hf; 
 between 0.05 and 1.0 wt % Si; 
 between 0.01 and 0.5 wt % of a fourth sum of rare earths of which at least two are present in the alloy, and at most 0.3 wt % of any rare earth; and 
 remainder Ni and unavoidable impurities. 
 
     
     
         26 . The nickel base γ/γ′ superalloy according to  claim 25 , wherein Y is present only as an unavoidable impurity. 
     
     
         27 . The nickel base γ/γ′ superalloy according to  claim 25 , further comprising:
 between 4.5 and 5.5 wt % Co, 
 between 18.2 and 19 wt % Cr, 
 between 1.4 and 1.8 wt % W, 
 between 5.2 and 5.5 wt % Al, 
 between 2.8 and 3.6 wt % Ta, 
 between 0.015 and 0.025 wt % C, 
 between 0.04 and 0.07 wt % Zr, 
 between 0.25 and 0.4 wt % Hf, 
 between 0.07 and 0.13 wt % Si, 
 between 0.05 and 0.15 wt % the fourth sum of La and Y, 
 at least 0.02 wt % La, and 
 at least 0.02 wt % Y. 
 
     
     
         28 . The nickel base γ/γ″ superalloy according to  claim 26 , further comprising:
 between 4.5 and 5.5 wt % Co, 
 between 18.2 and 19 wt % Cr, 
 between 1.4 and 1.8 wt % W, 
 between 5.2 and 5.5 wt % Al, 
 between 2.8 and 3.6 wt % Ta, 
 between 0.015 and 0.025 wt % C, 
 between 0.04 and 0.07 wt % Zr, 
 between 0.25 and 0.4 wt % Hf, 
 between 0.07 and 0.13 wt % Si, 
 and between 0.05 and 0.5 wt % of the fourth sum of rare earths, 
 at most 0.3 of any rare earth, and 
 La and Y present only as impurities. 
 
     
     
         29 . The nickel base γ/γ′ superalloy according to  claim 28 , further comprising:
 about 5 wt % Co, 
 about 18.5 wt % Cr, 
 about 1.6 wt % W, 
 about 5.3 wt % Al, 
 about 3.2 wt % Ta, 
 about 0.02 wt % C, 
 about 0.05 wt % Zr, 
 about 0.3 wt % Hf, 
 about 0.1 wt % Si, 
 about 0.05 wt % Ce, and 
 about 0.05 wt % Gd. 
 
     
     
         30 . The nickel base γ/γ′ superalloy according to  claim 26 , further comprising:
 between 4.5 and 5.5 wt % Co, 
 between 18.2 and 19 wt % Cr, 
 between 0.8 and 1.2 wt % Mo, 
 between 5.2 and 5.5 wt % Al, 
 between 2.8 and 3.6 wt % Ta, 
 between 0.015 and 0.025 wt % C, 
 between 0.04 and 0.07 wt % Zr, 
 between 0.25 and 0.4 wt % Hf, 
 between 0.07 and 0.13 wt % Si, 
 between 0.05 and 0.5 wt % of the fourth sum of Ce and Gd, 
 at least 0.02 wt % Ce, 
 at least 0.02 wt % Gd, and 
 at most 0.3 wt % of Ce or Gd. 
 
     
     
         31 . The nickel base γ/γ′ superalloy according to  claim 26 , further comprising:
 between 4.5 and 5.5 wt % Co, 
 between 20.2 and 20.8 wt % Cr, 
 between 0.8 and 1.2 wt % W, 
 between 4.8 and 5.2 wt % Al, 
 between 1.8 and 2.2 wt % Ta, 
 between 0.015 and 0.025 wt % C, 
 between 0.04 and 0.07 wt % Zr, 
 between 0.25 and 0.4 wt % Hf, 
 between 0.3 and 0.5 wt % Si, 
 between 0.05 and 0.5 wt % of the fourth sum of rare earths, and 
 wherein La and Y present only as impurities. 
 
     
     
         32 . The nickel base γ/γ′ superalloy according to  claim 31 , further comprising:
 about 5 wt % Co, 
 about 20.5 wt % Cr, 
 about 1 wt % W, 
 about 5 wt % Al, 
 about 2 wt % Ta, 
 about 0.02 wt % C, 
 about 0.05 wt % Zr, 
 about 0.3 wt % Hf, 
 about 0.4 wt % Si, 
 about 0.05 wt % Ce, and 
 about 0.05 wt % Gd. 
 
     
     
         33 . A component to be used in a hot environment, comprising:
 a nickel base γ/γ′ superalloy according to  claim 25 .   
     
     
         34 . The component according to  claim 33 , wherein the component is a filler alloy for repair welding of such hot components. 
     
     
         35 . The component according to  claim 33 , wherein the component is a filler alloy for cladding of such hot components. 
     
     
         36 . The component according to  claim 33 , wherein the component is a protective coating and/or bond coat in TBC systems on such hot components. 
     
     
         37 . The component according to  claim 33 , wherein the component is in dual use as coating and/or bond coat in a TBC system, and, as a filler alloy for repair welding on such hot components. 
     
     
         38 . The component according to  claim 33 , wherein the component is in dual use as coating and/or bond coat in a TBC system, and, as a filler alloy for cladding on such hot components. 
     
     
         39 . The component according to  claim 33 , wherein the component is an intermediate layer between the base alloy and a coating and/or a bond coat in a TBC system on such hot components. 
     
     
         40 . The component according to  claim 33 , wherein the nickel base γ/γ′ superalloy is in equiaxed form. 
     
     
         41 . The component according to  claim 33 , wherein the nickel base γ/γ′ superalloy is in directionally solidified form. 
     
     
         42 . The component according to  claim 33 , wherein the nickel base γ/γ′ superalloy is in single crystal form. 
     
     
         43 . The component according to  claim 33 , wherein the nickel base γ/γ′ superalloy is produced by a production process resulting in an S content below 10 ppmw in the alloy.