High temperature alloys

Abstract

Nickel base superalloys in which critical amounts of boron are employed to enhance creep-rupture strength and ductility in the 1,300° F-1,800° F. temperature range. Creep-rupture strength and ductility at temperatures around 1,800° F. also is enhanced by employing amounts of carbon below a critical upper limit. These alloys are particularly useful in the form of castings as gas turbine engine components.

What is claimed is: .[. 
     
       1.  A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:Elements           Percent______________________________________Chromium           5-22Aluminum           0.2-8Titanium           0.5-7Boron              0.07-0.25Carbon             less than 0.05%Cobalt             0.00-20Columbium          0.00-3Molybdenum         0.00-8Tantalum           0.00-10Vanadium           0.00-2Tungsten           0.00-20Rhenium            0.00-2Zirconium          0.00-1.00______________________________________ the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount of from about 35% to 85% by weight..]. .[.2. The nickel base alloy of claim 1 wherein the carbon content is no more than 0.025% by weight..]. .[.3. the nickel base alloy of claim 1 wherein the boron content is about 0.075% to 0.2% by weight..]. .[.4. A cast component for use in a gas turbine engine formed of the alloy of claim 1..]. .[.5. The component of claim 4 in which said component is a turbine blade..]. .[.6. The component of claim 4 in which said component is a disk..]. .[.7. The component of claim 4 in which said component is an integral wheel comprising a disk and turbine blade..]. .[.8. A cast component for use in a gas turbine engine formed of the alloy of claim 3..]. .[.9. The component of claim 8 wherein said component is a turbine blade..]. .[.10. The component of claim 8 wherein said component is a disk..]. .[.11. The component of claim 8 wherein said component is an integral wheel comprising a disk and turbine   
     
     
        blade..]. 12. A shaped object of the alloy of claim .[.1.]. .Iadd.50 .Iaddend.capable of withstanding an applied stress of 94,000 psi at 
     
     
        1,400°F. without rupture for a time in excess of 120 hours. 13. A shaped object of the alloy of claim .[.1.]. .Iadd.12 .Iaddend.capable of withstanding an applied stress of 29,000 psi at 1,800°F. without 
     
     
        rupture for a time in excess of 40 hours. 14. The alloy of claim .[.1.]. .Iadd.50 .Iaddend.which contains, on a weight basis, about 6.0% to about 17% chromium, about 2% to about 8% aluminum, .[.about 0.75% to about 3% titanium, about 2% to about 17% cobalt,.]. and about 40% to 80% by weight 
     
     
        nickel. 15. The nickel base alloy of claim 14 wherein the carbon content 
     
     
        is no more than 0.025% by weight. 16. A cast component for use in a gas 
     
     
        turbine engine formed of the alloy of claim 14. 17. A cast component for 
     
     
        use in a gas turbine engine formed of the alloy of claim 15. 18. The alloy of claim .[.1.]. .Iadd.50 .Iaddend.which contains, on a weight basis, about 5% to 12% chromium, about 4% to about 8% aluminum, .[.about 0.75% to about 2.5% titanium,.]. about 5% to about 15.5% cobalt, and about 40% to 
     
     
        80% by weight nickel. 19. The nickel base alloy of claim 18 wherein the 
     
     
        carbon content is no more than 0.025 by weight. 20. A cast component for 
     
     
        use in a gas turbine engine formed of the alloy of claim 18. 21. A cast component for use in a gas turbine engine formed of the alloy of claim 19. 
     
     
        2. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   Elements            Percent                                               
______________________________________                                    
Chromium            6 - 17                                                
Aluminum            2 - 8                                                 
Titanium            0.75 - 3                                              
Boron               0.05 - 0.3                                            
Carbon              0.00 - 0.05                                           
Cobalt              2 - 17                                                
Columbium           0.25 - 3                                              
Molybdenum          0.00- 3                                               
Tantalum            0.00 - 3                                              
Tungsten            5 - 20                                                
Zirconium           0.001 - 0.5                                           
______________________________________                                    
     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount   
     
     
        of from about 40% to 80% by weight. 23. The nickel base alloy of claim 22 
     
     
        wherein the boron content is about 0.07% to about 0.25% by weight. 24. The nickel base alloy of claim 22 wherein the carbon content is no more than 
     
     
        0.025 by weight. 25. A cast component for use in a gas turbine engine 
     
     
        formed of the alloy of claim 22. 26. A cast component for use in gas 
     
     
        turbine engine formed of the alloy of claim 24. 27. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   Elements            Percent                                               
______________________________________                                    
Chromium            8 - 10.25                                             
Aluminum            4.75 - 5.5                                            
Titanium            1 - 2.5                                               
Boron               0.05 - 0.3                                            
Carbon              0.00 - 0.05                                           
Cobalt              8 - 12                                                
Columbium           0.75 - 1.8                                            
Tungsten            11 - 16                                               
Zirconium           0.00 - 0.20                                           
______________________________________                                    
     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the   
     
     
        basic characteristics of the alloy. 28. The nickel base alloy of claim 27 
     
     
        wherein the boron content is about 0.07% to about 0.25% by weight. 29. The nickel base alloy of claim 27 wherein the carbon content is no more than 
     
     
        0.025% by weight. 30. A cast component for use in a gas turbine engine 
     
     
        formed of the alloy of claim 27. 31. The component of claim 30 in which 
     
     
        said component is a turbine blade. 32. A cast component for use in a gas 
     
     
        turbine engine formed of the alloy of claim 29. 33. The component of claim 
     
     
        32 wherein said component is a turbine blade. 34. A shaped object of the alloy of claim 27 capable of withstanding an applied stress of 94,000 psi at 1,400° F. without rupture for a time in excess of 120 hours. 
     
     
            A shaped object of the alloy of claim 29 capable of withstanding an applied stress of 29,000 psi at 1,800° F. without rupture for a 
     
     
        time in excess of 40 hours. 36. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   Elements            Percent                                               
______________________________________                                    
Chromium            5 - 12                                                
Aluminum            4 - 8                                                 
Titanium            0.75 - 2.5                                            
Boron               0.05 - 0.3                                            
Carbon              0.00 - 0.05                                           
Cobalt              5 - 15.5                                              
Columbium           0.00 - 0.20                                           
Molybdenum          3 - 8                                                 
Tantalum            2.3 - 10                                              
Tungsten            0.00 - 2.5                                            
Zirconium           0.00 - 1                                              
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     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount   
     
     
        of from about 40% to 80% by weight. 37. The nickel base alloy of claim 36 
     
     
        wherein the boron content is about 0.07% to about 0.25% by weight. 38. The nickel base alloy of claim 36 wherein the carbon content is no more than 
     
     
        0.025% by weight. 39. A cast component for use in a gas turbine engine 
     
     
        formed of the alloy of claim 36. 40. A cast component for use in a gas 
     
     
        turbine engine formed of the alloy of claim 38. 41. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   Elements            Percent                                               
______________________________________                                    
Chromium            7.5 - 8.5                                             
Aluminum            5.75 - 6.25                                           
Titanium            0.8 - 1.2                                             
Boron               0.05 - 0.3                                            
Carbon              0.00 - 0.05                                           
Cobalt              9.5 - 10.5                                            
Molybdenum          5.75 - 6.25                                           
Tantalum            4.0 - 4.5                                             
Zirconium           0.05 - 0.10                                           
______________________________________                                    
     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the   
     
     
        basic characteristics of the alloy. 42. The nickel base alloy of claim 41 
     
     
        wherein the boron content is about 0.07% to about 0.25% by weight. 43. The nickel base alloy of claim 41 wherein the carbon content is no more than 
     
     
        0.025% by weight. 44. A cast component for use in a gas turbine engine 
     
     
        formed of the alloy of claim 41. 45. The component of claim 44 in which 
     
     
        said component is a turbine blade. 46. A cast component for use in a gas 
     
     
        turbine engine formed of the alloy of claim 43. 47. The component of claim 
     
     
        46 wherein said component is a turbine blade. 48. A shaped object of the alloy of claim 41 capable of withstanding an applied stress of 94,000 psi at 1,400° F. without rupture for a time in excess of 120 hours. 
     
     
            A shaped object of the alloy of claim 43 capable of withstanding an applied stress of 29,000 psi at 1,800° F. without rupture for a 
     
     
        time in excess of 40 hours. 50. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   ELEMENTS            PERCENT                                               
______________________________________                                    
Chromium            5-22                                                  
Aluminum            0.2-8                                                 
Titanium            0.5-7                                                 
Boron               0.05-0.3                                              
Carbon              less than 0.05                                        
Cobalt              2-17                                                  
Columbium           0.00-3                                                
Molybdenum          0.00-8                                                
Tantalum            0.00-10                                               
Vanadium            0.00-2                                                
Tungsten            0.00-20                                               
Rhenium             0.00-2                                                
Zirconium           0.00-1.00                                             
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     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount   
     
     
        of from about 35% to 85% by weight. 51. The nickel base alloy of claim 50 
     
     
        wherein the boron content is about 0.07% to about 0.25% by weight. 52. The nickel base alloy of claim 51 wherein the carbon content is no more than 
     
     
        0.025% by weight. 53. A cast component for use in a gas turbine engine formed of the alloy of claim 50. .Iadd. 54. The nickel base alloy of claim 50 wherein the molybdenum content is 0.00 - 3% and the tungsten content is 5 - 20%. .Iaddend..Iadd. 55. The nickel base alloy of claim 50 wherein the molybdenum content is 3 - 8%, the tungsten content is < 2.5%, and the tantalum content is 2.3 - 10%. .Iaddend..Iadd. 56. The nickel base alloy of claim 50 wherein the cobalt content is 5 to 15.5% cobalt. .Iaddend. .Iadd. 57. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:   Elements           Percent                                                
______________________________________                                    
Chromium           5 - 12                                                 
Aluminum           2 - 8                                                  
Titanium           0.5 - 7                                                
Boron              0.05 - 0.3                                             
Carbon             less than 0.05%                                        
Cobalt             2 - 17                                                 
Columbium          0.00 - 3                                               
Molybdenum         0.00 - 8                                               
Tantalum           0.00 - 3                                               
Vanadium           0.00 - 2                                               
Tungsten           < 2.5                                                  
Rhenium            0.00 - 2                                               
Zirconium          0.00 - 1.00                                            
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     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount of from about 35% to 85% by weight. .Iaddend..Iadd. 58. The nickel base alloy of claim 57 wherein the tungsten and vanadium contents are essentially 0. .Iaddend..Iadd. 59. A cast component for use in a gas turbine engine formed of the alloy of claim 57. .Iaddend..Iadd. 60. The nickel base alloy of claim 57 wherein the carbon content is no more than 0.025% by weight. .Iaddend. .Iadd. 61. A nickel base alloy for use at relatively high temperatures consisting essentially of the following elements in the weight percent ranges set forth:     ELEMENTS            PERCENT                                               
______________________________________                                    
Chromium            5-22                                                  
Aluminum            0.2-8                                                 
Titanium            0.5-7                                                 
Boron               0.05-0.3                                              
Carbon              less than 0.05                                        
Columbium           0.00-3                                                
Cobalt              5-15.5                                                
Molybdenum          < 3                                                   
Tantalum            0-10                                                  
Vanadium            0.00-2                                                
Tungsten            0.00-20                                               
Rhenium             0.00-2                                                
Zirconium           0.00-1.00                                             
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     the balance of the alloy being essentially nickel and minor amounts of impurities and incidental elements which do not detrimentally affect the basic characteristics of the alloy, said nickel being present in an amount of from about 35% to 85% by weight. .Iaddend..Iadd. 62. The nickel base alloy of claim 61 wherein the carbon content is no more than 0.025% by weight. .Iaddend..Iadd. 63. The nickel base alloy of claim 61 wherein the chromium content is 5 - 12% and the tungsten content is 5 - 20%. .Iaddend. .Iadd. 64. The alloy of claim 61, which contains, on a weight basis, about 2.3% to about 10% tantalum. .Iaddend..Iadd. 65. The alloy of claim 64 which contains, on a weight basis, 5-20% tungsten. .Iaddend..Iadd. 66. The alloy of claim 61, which contains, on a weight basis, less than 3% tantalum. .Iaddend..Iadd. 67. The alloy of claim 14 which contains, on a weight basis, 0 to about 3% molybdenum, 0 to about 3% tantalum, about 5% to about 20% tungsten, and about 0.001 to about 0.5% zirconium. .Iaddend..Iadd. 68. The alloy of claim 18, which contains, on a weight basis, about 3% to about 8% molybdenum, about 2.3% to about 10% tantalum, and 0 to about 2.5% tungsten.