Nickel-base alloy for gas turbine components
A nickel-based alloy is disclosed which is suitable for casting gas turbine components having improved strength and comparative lower density while utilizing commercially available heat treatment cycles. The nickel-based alloy is suitable for providing equiaxed, directionally solidified, and single crystal castings. Methods of providing a cast article of the nickel-based alloy and subjecting the article to heat treatment cycles are also disclosed.
1. A nickel-based alloy for a gas turbine component, comprising:
3.0-4.0 wt. % aluminum (Al),
0.005-0.015 wt. % boron (B),
0.0-0.0001 wt. % bismuth (Bi),
0.03-0.05 wt. % carbon (C),
10.0-15.0 wt. % chromium (Cr),
10.0-15.0 wt. % cobalt (Co),
0.0-0.2 wt. % iron (Fe),
0.0-0.1 wt. % hafnium (Hf),
0.0-0.001 wt. % lead (Pb),
0.0-0.02 wt. % magnesium (Mg),
0.0-0.2 wt. % manganese (Mn),
1.0-3.0 wt. % molybdenum (Mo),
0.0-0.002 wt. % nitrogen (N),
0.1-0.2 wt. % niobium (Nb),
0.0-0.002 wt. % oxygen (O),
0.0-0.003 wt. % phosphorus (P),
0.0-0.0004 wt. % selenium (Se),
0.0-0.1 wt. % silicon (Si),
0.0-0.0003 wt. % silver (Ag),
0.0-0.005 wt. % sulfur (S),
2.5-3.5 wt. % tantalum (Ta),
0.0-0.0001 wt. % tellurium (Te),
4.0-5.0 wt. % titanium (Ti),
0.0003-0.001 wt. % thallium (Tl),
2.5-3.5 wt. % tungsten (W),
0.0-0.01 wt. % zirconium (Zr),
with the balance comprising nickel (Ni).
2. The alloy of claim 1 , wherein the alloy comprises:
3.35-3.65 wt. % aluminum (Al),
0.005-0.015 wt. % boron (B),
0.0-0.00005 wt. % bismuth (Bi),
0.035-0.05 wt. % carbon (C),
11.5-12.5 wt. % chromium (Cr),
11.5-12.5 wt. % cobalt (Co),
0.0-0.15 wt. % iron (Fe),
0.0-0.05 wt. % hafnium (Hf),
0.0-0.0005 wt. % lead (Pb),
0.0-0.01 wt. % magnesium (Mg),
0.0-0.1 wt. % manganese (Mn),
2.0-2.4 wt. % molybdenum (Mo),
0.0-0.00015 wt. % nitrogen (N),
0.1-0.2 wt. % niobium (Nb),
0.0-0.0015 wt. % oxygen (O),
0.0-0.002 wt. % phosphorus (P),
0.0-0.0003 wt. % selenium (Se),
0.0-0.06 wt. % silicon (Si),
0.0-0.0002 wt. % silver (Ag),
0.0-0.001 wt. % sulfur (S),
2.8-3.2 wt. % tantalum (Ta),
0.0-0.00005 wt. % tellurium (Te),
4.55-4.85 wt. % titanium (Ti),
0.0003-0.0005 wt. % thallium (Tl),
2.8-3.2 wt. % tungsten (W),
0.0-0.004 wt. % zirconium (Zr),
with the balance comprising nickel (Ni).
3. The alloy of claim 2 , wherein the Nv3B is less than 2.5.
4. The alloy of claim 3 , wherein the Nv3B is equal to or less than 2.4.
5. The alloy of claim 3 , wherein the density of the alloy is about 0.297-0.298 lb/in3.
6. The alloy of claim 2 , wherein the alloy comprises:
3.5 wt. % aluminum (Al),
0.012 wt. % boron (B),
0.00005 wt. % bismuth (Bi),
0.05 wt. % carbon (C),
12.0 wt. % chromium (Cr),
12.0 wt. % cobalt (Co),
0.15 wt. % iron (Fe),
0.05 wt. % hafnium (Hf),
0.0005 wt. % lead (Pb),
0.01 wt. % magnesium (Mg),
0.1 wt. % manganese (Mn),
2.2 wt. % molybdenum (Mo),
0.0015 wt. % nitrogen (N),
0.1 wt. % niobium (Nb),
0.0015 wt. % oxygen (O),
0.002 wt. % phosphorus (P),
0.0003 wt. % selenium (Se),
0.06 wt. % silicon (Si),
0.0002 wt. % silver (Ag),
0.0001 wt. % sulfur (S),
3.0 wt. % tantalum (Ta),
0.00005 wt. % tellurium (Te),
4.7 wt. % titanium (Ti),
0.0005 wt. % thallium (Tl),
3.0 wt. % tungsten (W),
0.0075 wt. % zirconium (Zr),
with the balance comprising nickel (Ni).
7. The alloy of claim 4 , wherein the Nv3B is 2.4.
8. The alloy of claim 2 , wherein the alloy comprises:
3.5 wt. % aluminum (Al),
0.01 wt. % boron (B),
0.00005 wt. % bismuth (Bi),
0.05 wt. % carbon (C),
12.0 wt. % chromium (Cr),
12.0 wt. % cobalt (Co),
0.15 wt. % iron (Fe),
0.05 wt. % hafnium (Hf),
0.0005 wt. % lead (Pb),
0.01 wt. % magnesium (Mg),
0.1 wt. % manganese (Mn),
2.2 wt. % molybdenum (Mo),
0.0015 wt. % nitrogen (N),
0.1 wt. % niobium (Nb),
0.0015 wt. % oxygen (O),
0.002 wt. % phosphorus (P),
0.0003 wt. % selenium (Se),
0.06 wt. % silicon (Si),
0.0002 wt. % silver (Ag),
0.0001 wt. % sulfur (S),
3.0 wt. % tantalum (Ta),
0.00005 wt. % tellurium (Te),
4.7 wt. % titanium (Ti),
0.0005 wt. % thallium (Tl),
3.0 wt. % tungsten (W),
0.004 wt. % zirconium (Zr),
with the balance comprising nickel (Ni).
9. The alloy of claim 8 , wherein the Nv3B is 2.4.
10. A nickel-based alloy for a gas turbine component, wherein the alloy comprises:
3.35-3.65 wt. % aluminum (Al);
0.005-0.015 wt. % boron (B);
0.0-0.00005 wt. % bismuth (Bi);
0.035-0.05 wt. % carbon (C);
11.5-12.5 wt. % each of chromium (Cr) and cobalt (Co);
0.0-0.15 wt. % iron (Fe);
0.0-0.05 wt. % hafnium (Hf);
0.0-0.0005 wt. % lead (Pb);
0.0-0.01 wt. % magnesium (Mg);
0.0-0.1 wt. % manganese (Mn);
2.0-2.4 wt. % molybdenum (Mo);
0.0-0.00015 wt. % nitrogen (N);
0.0-0.1 wt. % niobium (Nb);
0.0-0.0015 wt. % oxygen (O);
0.0-0.002 wt. % phosphorus (P);
0.0-0.0003 wt. % selenium (Se);
0.0-0.06 wt. % silicon (Si);
0.0-0.0002 wt. % silver (Ag);
0.0-0.001 wt. % sulfur (S);
2.8-3.2 wt. % tantalum (Ta);
0.0-0.00005 wt. % tellurium (Te);
4.55-4.85 wt. % titanium (Ti);
0.0003-0.0005 wt. % thallium (Tl);
2.8-3.2 wt. % tungsten (W);
0.0-0.004 wt. % zirconium (Zr); and
the remaining balance comprising nickel (Ni); and
wherein:
the alloy measures a 15% elongation, 4D after 80 hours at a temperature of 1800° F. in a directionally solidified form; and
the alloy measures a 10% elongation, 4D after 85 hours at a temperature of 1800° F. in a single crystal form.
11. The alloy of claim 10 , wherein the density of the alloy is 0.297-0.298 lb/in3.
12. The alloy of claim 10 , wherein the Nv3B is equal to or less than 2.4.
13. The alloy of claim 10 , wherein the yield strength of the alloy at 1200° F. is greater than 110 ksi.
14. The alloy of claim 10 , wherein the alloy measures a 20% reduction in area after 80 hours at a temperature of 1800° F. in the directionally solidified form.
15. The alloy of claim 14 , wherein the alloy measures a 10% reduction in area after 85 hours at a temperature of 1800° F. in the single crystal form.
16. A method of forming a single crystal alloy investment casting component for a gas turbine engine, comprising:
(a) providing a nickel-based alloy for casting the component, the alloy comprising:
about 3.5 wt. % aluminum (Al),
about 0.01 wt. % boron (B),
about 0.00005 wt. % bismuth (Bi),
about 0.05 wt. % carbon (C),
about 12.0 wt. % chromium (Cr),
about 12.0 wt. % cobalt (Co),
about 0.15 wt. % iron (Fe),
about 0.05 wt. % hafnium (Hf),
about 0.0005 wt. % lead (Pb),
about 0.01 wt. % magnesium (Mg),
about 0.1 wt. % manganese (Mn),
about 2.2 wt. % molybdenum (Mo),
about 0.0015 wt. % nitrogen (N),
about 0.1 wt. % niobium (Nb),
about 0.0015 wt. % oxygen (O),
about 0.002 wt. % phosphorus (P),
about 0.0003 wt. % selenium (Se),
about 0.06 wt. % silicon (Si),
about 0.0002 wt. % silver (Ag),
about 0.001 wt. % sulfur (S),
about 3.0 wt. % tantalum (Ta),
about 0.00005 wt. % tellurium (Te),
about 4.7 wt. % titanium (Ti),
about 0.0005 wt. % thallium (Tl),
about 3.0 wt. % tungsten (W),
about 0.004 wt. % zirconium (Zr),
with the balance comprising nickel (Ni); and
(b) subjecting the component to a heat treatment within 8 deg. of <001> direction, wherein the heat treatment comprises the steps of:
(1) heating the specimen to 2225° F.+/−25° F. at 20,000 psi+/−500 psi for 4 hours+/−15 minutes;
(2) solutioning at 2050° F.+/−25° F. and subsequently ramping to 2250° F.+/−15° F. at a maximum of 5° F. per minute, and holding this temperature for at least 2 hours;
(3) cooling, via gas quench, to 1500° F. at more than 75° F. per minute and from 1500° F. to below 1200° F. at 10° F. per minute or faster;
(4) heating to 2050° F.+/−25° F. for 2 hours;
(5) cooling to 1000° F. at a rate equivalent to air cooling, or faster;
(6) elevating to 1550° F.+/−25° F. and holding for at least 24 hours; and
(7) cooling to 1000° F. or below.
17. The method of claim 16 , wherein the component measures a 10% elongation, 4D after 85 hours at temperatures greater than 1600° F.
18. The method of claim 16 , wherein the gas quench gas for cooling is argon gas.
19. The method of claim 17 , wherein the component measures a 10% reduction in area after 85 hours at temperatures greater than 1600° F.
20. The method of claim 16 , wherein the component measures a 10% elongation, 4D and a 10% reduction in area after 85 hours at temperatures greater than 1600° F.