Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     FIELD OF THE DISCLOSURE 
     Nickel-base superalloys for single crystal castings exhibiting a balanced combination of outstanding properties are disclosed. 
     BACKGROUND OF THE DISCLOSURE 
     There is a continuing demand for advanced gas turbines that achieve lower fuel burn rates and commensurate reduced carbon dioxide exhaust emissions. Therefore, there remains a pressing need for superalloys that can be cast into complex cooled turbine blades and vanes that are capable of operating at higher gas and metal temperatures. These castings desirably exhibit a combination of high strength, excellent high temperature, creep-rupture properties, and good phase stability. 
     Single crystal nickel-base superalloys typically contain high levels of refractory elements such as molybdenum, tungsten, rhenium and tantalum in order to improve high temperature creep-rupture properties. However, high levels of these elements can result in topologically close-packed (TCP) phase formation during high temperature stressed exposure, which can be associated with the development of sites for premature crack initiation, resulting in a degradation of long term creep-rupture properties. As such, the selection of appropriate levels of refractory elements and chromium content involves a delicate balancing of strength properties against long term phase stability. The TCP phases are rhenium and tungsten rich with some chromium. Excessive formation of TCP phases de-alloy the material, thus lowering the creep-rupture strength. 
     The highest strength nickel-base superalloys for single crystal castings for use in flight engines contain about 5% to about 7% rhenium by weight. These include CMSX-10K® and CMSX-10N® alloys, developed and available from Cannon-Muskegon Corporation and described in U.S. Pat. Nos. 5,366,645 and 5,540,790, and Rene N-6 alloy, developed by the General Electric Company. However, these specialty, high-strength nickel-base superalloys have exhibited certain undesirable features for particular applications. These alloys tend to develop a type of phase instability due to the high rhenium-content, which is known as a secondary reaction zone (SRZ) instability, that is observed in the base alloy adjacent to the coatings, which results in coating compatibility and thin-wall mechanical property issues. Additionally, CMSX-10K® and CMSX-10N® alloys have a very low chromium content (1.5% and 2.2% by weight respectively) to accommodate the high rhenium content, which consequently reduces low temperature internal oxidation resistance and hot corrosion resistance. These alloys also have high γ′ solvus temperatures, requiring a very high temperature solution heat treatment, which can cause surface melting issues. These alloys also tend to have a relatively high density, which is a significant weight and inertia disadvantage for flight engines, especially for rotating turbine blades. These very high strength specialty alloys are also expensive due to the high price of rhenium, which has approximately quadrupled in the last 20 years. 
     SUMMARY OF THE DISCLOSURE 
     The disclosed alloys were designed and developed to provide a single crystal casting with creep and fatigue properties similar to the very high strength nickel-base superalloys containing about 5% to about 7% rhenium by weight, but which contain substantially less rhenium, thereby eliminating SRZ phase instability issues, improving low temperature internal oxidation resistance and hot corrosion resistance, reducing the γ′ solvus temperature, reducing density, reducing cost, and providing a combination of these advantages, and while also providing significantly improved high temperature creep-rupture properties as compared to a CMSX-4® alloy containing 3% rhenium by weight. 
     The disclosed alloys exhibiting improved properties contain 5.60% to 5.80% by weight of aluminum; 9.4% to 9.8% by weight of cobalt; 3.2% to 3.9% by weight of chromium; 7.8% to 8.5% by weight of tantalum; 5.3% to 5.7% by weight of tungsten; 0.50% to 0.70% by weight of molybdenum; 4.3% to 4.9% by weight of rhenium; 0.75% to 0.90% by weight of titanium; 0.08% to 0.15% by weight of hafnium; less than 1.1% by weight of tramp elements other than aluminum, cobalt, chromium, tantalum, tungsten, molybdenum, rhenium, titanium and nickel; and the balance nickel. 
     In certain aspects of this disclosure, the nickel-base superalloy contains a total amount of tantalum, molybdenum, tungsten and rhenium of from 18.2% to 19.5% by weight. 
     In certain aspects of this disclosure, the nickel-base superalloy contains a total amount of aluminum, titanium and tantalum that is from 14.25% to 15.0% by weight. 
     In certain aspects of this disclosure, the nickel-base superalloy contains the following maximum amounts by weight of elements: 100 ppm carbon, 0.04% silicon, 0.01% manganese, 3 ppm sulfur, 30 ppm phosphorus, 30 ppm boron, 0.15% niobium, 150 ppm zirconium, 0.01% copper, 0.15% iron, 0.10% vanadium, 0.15% ruthenium, 0.25% platinum, 0.20% palladium, 0.02% magnesium, 5 ppm nitrogen, 5 ppm oxygen, 2 ppm silver, 0.2 ppm bismuth, 10 ppm gallium, 25 ppm calcium, 1 ppm lead, 0.5 ppm selenium, 0.2 ppm tellurium, 0.2 ppm thallium, 10 ppm tin, 2 ppm antimony, 2 ppm arsenic, 5 ppm zinc, 2 ppm mercury, 0.2 ppm cadmium, 0.2 ppm indium, 2 ppm germanium, 2 ppm gold, 20 ppm sodium, 10 ppm potassium, 10 ppm barium, 2 ppm thorium, and 2 ppm uranium. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a graph of yield strength and ultimate tensile strength as a function of temperature for an alloy as disclosed herein. 
         FIG. 2  is a graph of percent elongation and percent reduction in area for an alloy as disclosed herein. 
         FIGS. 3 and 4  are Larson-Miller plots comparing alloys according to this disclosure with commercially available alloys widely used in high temperature, high stress gas turbine applications. 
         FIGS. 5 and 6  are optical photographs of a CMSX-4® PLUS (MOD A) single crystal test bar (#52JFT) that was fully heat treated. 
         FIGS. 7 and 8  are scanning electron micrographs of the CMSX-4® PLUS (MOD A) single crystal test bar (#52JFT) that was fully heat treated. 
         FIGS. 9 and 10  are optical photographs of a CMSX-4® PLUS (MOD B) single crystal test bar (#M975) that was solutioned and primary aged. 
         FIGS. 11 and 12  are scanning electron micrographs of the CMSX-4® PLUS (MOD B) single crystal test bar (#M975) that was solutioned and primary aged. 
         FIGS. 13 and 14  are optical photographs of a CMSX-4® PLUS (MOD C) single crystal test bar (#B981) that was fully heat treated. 
         FIGS. 15 and 16  are scanning electron micrographs of the CMSX-4® PLUS (MOD C) single crystal test bar (#N978) that was fully heat treated. 
         FIGS. 17 and 18  are optical photographs of a CMSX-4® PLUS (MOD C) single crystal test bar (#N978) that was fully heat treated and stress-rupture tested. 
     
    
    
     DETAILED DESCRIPTION 
     The high strength nickel-base superalloys for single crystal casting of this disclosure will be designated “CMSX-4® PLUS” alloys. 
     The alloy chemistry is developed from that of CMSX®-8 alloy (CM Tech Papers TMS Seven Spring Superalloy Symposium, September 2012; and ASME Turbo Expo, Dusseldorf, June 2014). The CMSX®-8 alloy exhibits excellent single crystal castability and high temperature oxidation resistance. This 1.5% by weight rhenium containing alloy has creep-rupture properties close to but somewhat less than CMSX-4® alloy. 
     Rhenium content was selected about 4% with the objective of providing a desirable balance between appreciably enhancing high temperature creep-rupture properties over CMSX-4®, and undesirably promoting SRZ phase occurrence under coatings and excessive TCP phase formation in turbine components during high temperature, stressed exposure. 
     A Cr content of about 3% to about 4% was selected to promote low temperature oxidation and hot corrosion (sulfidation) resistance. 
     The Mo content was critically left low at 0.60% to avoid oxidation issues. This necessitated using Ti in the alloy in range of 0.75-0.90% to ensure appropriate γ/γ′ mis-match and interfacial chemistry and hence ensure approximately 0.5 μm cubic, aligned γ′ for solutioned/homogenized and high temperature primary age heat treated microstructures. This maximizes creep-rupture properties. Ti also reduces alloy density. The Ti content additionally improves transformation potential as part of the raw material mix. 
     Ta content was maintained as per CMSX®-8 alloy in the 8% regime to maximize single crystal castability/airfoil component casting yield, by minimizing propensity for “freckle-chain” grain defects and avoiding the necessity for unduly high W content (maintained in the 5.0-5.5% regime). High W encourages “freckle” formation and reduces oxidation resistance. Ta is also an active γ′ former (simplified γ′ composition Ni 3  (Al, Ti, Ta)), besides being a powerful, large atom, solid solution strengthener. 
     Hf was maintained at about 0.10% to ensure acceptable solution heat treat “windows” for these highly alloyed CMSX-4® Plus chemistry compositions. Hf improves coating performance under oxidizing conditions, but reduces incipient melting point greater than its reduction in γ′ solvus temperature. This effect increases with higher Hf levels. 
     The 470 lb 100% virgin (100V) VIM heats were made at Cannon-Muskegon Corporation using state of the art melting practices and very high purity materials for this alloy development program, which were all made with the following tight controls on deleterious trace elements: 
     Wt PPM 
     
       
         
               
               
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 Ag 
                 &lt;.4 
                 U 
                 &lt;.5 
               
               
                   
                 Bi 
                 &lt;.1 
                 Th 
                 &lt;1 
               
               
                   
                 Ga 
                 &lt;10 
                 Cd 
                 &lt;.2 
               
               
                   
                 Pb 
                 &lt;.5 
                 Ge 
                 &lt;1 
               
               
                   
                 Se 
                 &lt;.5 
                 Pt 
                 &lt;.005% 
               
               
                   
                 Te 
                 &lt;.2 
                 Au 
                 &lt;.5 
               
               
                   
                 Tl 
                 &lt;.2 
                 In 
                 &lt;.2 
               
               
                   
                 Sn 
                 &lt;2 
                 Na 
                 &lt;10 
               
               
                   
                 Sb 
                 &lt;1 
                 K 
                 &lt;5 
               
               
                   
                 As 
                 &lt;1 
                 Ca 
                 &lt;10 
               
               
                   
                 Zn 
                 &lt;1 
                 Ba 
                 &lt;5 
               
               
                   
                 Hg 
                 &lt;2 
                 Mg 
                 &lt;200 ppm 
               
               
                   
                   
               
             
          
         
       
     
     CMSX-4® Plus (Mod A) 
     A 470 lb VIM heat (100V) [5V0603] was made in the CM V-5 furnace in February 2013. The heat chemistry, which was very close to the design target, is shown below: 
     
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 5V0603 
                 RR Corpn. DL-10 
                 SMP SX Test Bar 
               
               
                   
                 Heat Chemistry 
                 Test Bar Mold #968 
                 Mold 52J . . . 
               
               
                   
                 Wt % or PPM 
                 Wt % or PPM 
                 Wt % or PPM 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                 C 
                 21 ppm  
                 26 ppm  
                 31 ppm  
               
               
                 S 
                 1 ppm 
                 1 ppm 
                 1 ppm 
               
               
                 Si 
                 &lt;.01 
                 .01 
                 .01 
               
               
                 Mn 
                 &lt;.001 
                 &lt;.01 
                 &lt;.01 
               
               
                 Al 
                 5.80 
                 5.73 
                 5.70 
               
               
                 B 
                 &lt;20 ppm    
                 &lt;20 ppm    
                 &lt;20 ppm    
               
               
                 Cb 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
               
               
                 Co 
                 9.7 
                 9.6 
                 9.7 
               
               
                 Cr 
                 4.2 
                 4.3 
                 4.2 
               
               
                 Cu 
                 &lt;.001 
                 &lt;.001 
                 &lt;.001 
               
               
                 Fe 
                 .015 
                 &lt;.05 
                 &lt;.05 
               
               
                 Hf 
                 .13 
                 .14 
                 .13 
               
               
                 Mo 
                 .60 
                 .61 
                 .61 
               
               
                 Ni 
                 BAL 
                 BAL 
                 BAL 
               
               
                 [N] 
                 1 ppm 
                 1 ppm 
                 2 ppm 
               
               
                 [O] 
                 1 ppm 
                 2 ppm 
                 2 ppm 
               
               
                 P 
                 6 ppm 
                 10 ppm  
                 6 ppm 
               
               
                 Re 
                 4.0 
                 3.9 
                 4.0 
               
               
                 Ru 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
               
               
                 Ta 
                 8.4 
                 8.4 
                 8.4 
               
               
                 Ti 
                 .66 
                 .67 
                 .65 
               
               
                 W 
                 5.3 
                 5.4 
                 5.3 
               
               
                 Zr 
                 &lt;25 ppm    
                 &lt;25 ppm    
                 &lt;25 ppm    
               
               
                 V 
                 &lt;.005 
                 &lt;.01 
                 &lt;.01 
               
               
                 Y 
                 &lt;.001 
                 — 
                 — 
               
               
                 La 
                 &lt;.001 
                 — 
                 — 
               
               
                 Ce 
                 &lt;.002 
                 — 
                 — 
               
               
                 Mg 
                 &lt;200 ppm    
                 2 ppm 
                 1 ppm 
               
               
                 [Ta + W + 
                 18.30 
                 18.31 
                 18.31 
               
               
                 Mo + Re] 
               
               
                 [Al + Ti] 
                 6.46 
                 6.40 
                 6.35 
               
               
                 [Al + Ti + Ta] 
                 14.86 
                 14.80 
                 14.75 
               
               
                   
               
             
          
         
       
     
     Single crystal test bars (within 10° of (001)) were successfully cast using established CMSX-4® casting parameters at two production single crystal foundries (Rolls-Royce Corporation and SMP (PCC Airfoils)) with high yields and excellent chemistry retention. 
     Multi-step solutioning/homogenization and high temperature primary aging steps were researched to develop the microstructures shown in  FIGS. 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16 . 
     The peak solution-homogenization temperature selected was 2435° F. (1335° C.)—(6 hrs) with primary age of 2085° F. (1140° C.)—(6 hrs). 
     All single crystal specimen machining (low stress grinding) and creep-stress-rupture testing were undertaken by Joliet Metallurgical Labs, Joliet, Ill. 
     The creep-rupture properties attained with Mod A although improved compared to CMSX-4® up to 1922° C. (1050° C.), were well short of the target properties (Table 1 and Tables 4, 5 and 6). 
     CMSX-4® Plus (Mod B) 
     To target higher creep-rupture properties, a 470 lb heat (100V) [5V0636] was made in the CM V-5 furnace in July 2013. 
     The heat chemistry which was very close to the design target, is shown below. 
     
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                   
                   
                 RR Corpn. 
                 RR Corpn. 
                 RR Corpn. 
               
               
                   
                 5V0636 
                 RR Corpn. 
                 DL-10 
                 DL-10 
                 DL-10 
               
               
                   
                 Heat 
                 DL-10 
                 Test Bar 
                 Test Bar 
                 Test Bar 
               
               
                   
                 Chemistry 
                 Test Bar Mold 
                 Mold #977 
                 Mold #982 
                 Mold #983 
               
               
                   
                 Wt % or 
                 #968 
                 Wt % or 
                 Wt % or 
                 Wt % or 
               
               
                   
                 PPM 
                 Wt % or PPM 
                 PPM 
                 PPM 
                 PPM 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                 C 
                 16 ppm  
                 41 ppm  
                 30 ppm  
                 78 ppm  
                 47 ppm  
               
               
                 S 
                 1 ppm 
                 1 ppm 
                 1 ppm 
                 1 ppm 
                 1 ppm 
               
               
                 Si 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
                 .02 
               
               
                 Mn 
                 &lt;.001 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
               
               
                 Al 
                 5.71 
                 5.62 
                 5.68 
                 5.70 
                 5.70 
               
               
                 B 
                 &lt;20 ppm    
                 &lt;20 ppm    
                 &lt;20 ppm    
                 &lt;20 ppm    
                 &lt;20 ppm    
               
               
                 Cb 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
               
               
                 Co 
                 9.6 
                 9.6 
                 9.6 
                 9.6 
                 9.5 
               
               
                 Cr 
                 3.7 
                 3.7 
                 3.7 
                 3.7 
                 3.6 
               
               
                 Cu 
                 &lt;.001 
                 &lt;.001 
                 &lt;.001 
                 &lt;.001 
                 &lt;.001 
               
               
                 Fe 
                 .012 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
               
               
                 Hf 
                 .10 
                 .11 
                 .10 
                 .10 
                 .10 
               
               
                 Mo 
                 .60 
                 .61 
                 .60 
                 .60 
                 .60 
               
               
                 Ni 
                 BAL 
                 BAL 
                 BAL 
                 BAL 
                 BAL 
               
               
                 [N] 
                 1 ppm 
                 1 ppm 
                 1 ppm 
                 1 ppm 
                 1 ppm 
               
               
                 [O] 
                 1 ppm 
                 3 ppm 
                 1 ppm 
                 3 ppm 
                 2 ppm 
               
               
                 P 
                 4 ppm 
                 8 ppm 
                 8 ppm 
                 1 ppm 
                 1 ppm 
               
               
                 Re 
                 4.55 
                 4.53 
                 4.52 
                 4.47 
                 4.47 
               
               
                 Ru 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
                 — 
                 — 
               
               
                 Ta 
                 8.0 
                 8.0 
                 8.0 
                 8.0 
                 8.0 
               
               
                 Ti 
                 .82 
                 .81 
                 .82 
                 .82 
                 .81 
               
               
                 W 
                 5.5 
                 5.5 
                 5.5 
                 5.5 
                 5.5 
               
               
                 Zr 
                 &lt;25 ppm    
                 &lt;25 ppm    
                 &lt;25 ppm    
                 &lt;.005 
                 &lt;.005 
               
               
                 V 
                 &lt;.005 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
                 &lt;.01 
               
               
                 Y 
                 &lt;.001 
                 — 
                 — 
                 — 
                 — 
               
               
                 La 
                 &lt;.001 
                 — 
                 — 
                 — 
                 — 
               
               
                 Ce 
                 &lt;.002 
                 — 
                 — 
                 — 
                 — 
               
               
                 Mg 
                 &lt;200 ppm    
                 2 ppm 
                 2 ppm 
                 2 ppm 
                 2 ppm 
               
               
                 [Ta + W + Mo + Re] 
                 18.65 
                 18.64 
                 18.62 
                 18.57 
                 18.57 
               
               
                 [Al + Ti] 
                 6.53 
                 6.43 
                 6.50 
                 6.52 
                 6.51 
               
               
                 [Al + Ti + Ta] 
                 14.53 
                 14.43 
                 14.50 
                 14.52 
                 14.51 
               
               
                   
               
             
          
         
       
     
     The creep-rupture properties attained with Mod B are now much more interesting which are well above CMSX-4® up to 1922° F. (1050° C.) (Table 2, 4, 5 and 6). 
     The full heat treatment conditions were “fine-tuned” from the previous Mod A work, with a peak solution/homogenization temperature of 2435° F. (1335° C.)—(6 hrs) and 2085° F. (1140° C.)—(6 hrs) primary age. 
     The density of the Mod B composition was determined by NPL in the UK to be 8.89 kg/dm 3  compared to 9.05 for CMSX-10K® (6.3% Re) and 8.95 for PWA 1484 (3% Re). 
     CMSX-4® Plus (Mod C) 
     To fully explore the potential of the chemistry development/performance concepts of this new alloy system, a further 470 lb heat [100V] [5V0660] was made in the Cannon-Muskegon Corporation V-5 furnace in October 2013. The heat chemistry which again was very close to the design target, is shown below: 
     
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                   
                   
               
               
                   
                   
                   
                 RR Corpn. DL-10 
               
               
                   
                 5V0660 
                 RR Corpn. DL-10 
                 Test Bar Mold 
               
               
                   
                 Heat Chemistry 
                 Test Bar Mold #978 
                 #981 
               
               
                   
                 Wt % or PPM 
                 Wt % or PPM 
                 Wt % or PPM 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                 C 
                 19 ppm  
                 51 ppm  
                 66 ppm  
               
               
                 S 
                 1 ppm 
                 1 ppm 
                 1 ppm 
               
               
                 Si 
                 &lt;.01 
                 .02 
                 .01 
               
               
                 Mn 
                 &lt;.001 
                 &lt;.01 
                 &lt;.01 
               
               
                 Al 
                 5.73 
                 5.68 
                 5.70 
               
               
                 B 
                 &lt;20 ppm    
                 &lt;20 ppm    
                 &lt;20 ppm    
               
               
                 Cb 
                 &lt;.05 
                 &lt;.05 
                 &lt;.05 
               
               
                 Co 
                 9.6 
                 9.6 
                 9.6 
               
               
                 Cr 
                 3.5 
                 3.5 
                 3.5 
               
               
                 Cu 
                 &lt;.001 
                 &lt;.001 
                 &lt;.001 
               
               
                 Fe 
                 .010 
                 &lt;.05 
                 &lt;.05 
               
               
                 Hf 
                 .10 
                 .10 
                 .12 
               
               
                 Mo 
                 .60 
                 .60 
                 .60 
               
               
                 Ni 
                 BAL 
                 BAL 
                 BAL 
               
               
                 [N] 
                 1 ppm 
                 2 ppm 
                 1 ppm 
               
               
                 [O] 
                 1 ppm 
                 2 ppm 
                 2 ppm 
               
               
                 P 
                 4 ppm 
                 7 ppm 
                 1 ppm 
               
               
                 Re 
                 4.87 
                 4.81 
                 4.83 
               
               
                 Ru 
                 &lt;.01 
                 — 
                 — 
               
               
                 Ta 
                 8.2 
                 8.2 
                 8.2 
               
               
                 Ti 
                 .86 
                 .86 
                 .86 
               
               
                 W 
                 5.5 
                 5.5 
                 5.5 
               
               
                 Zr 
                 &lt;25 ppm    
                 &lt;25 ppm    
                 &lt;25 ppm    
               
               
                 V 
                 &lt;.005 
                 &lt;.010 
                 &lt;.010 
               
               
                 Y 
                 &lt;.001 
                 — 
                 — 
               
               
                 La 
                 &lt;.001 
                 — 
                 — 
               
               
                 Ce 
                 &lt;.002 
                 — 
                 — 
               
               
                 Mg 
                 &lt;200 ppm    
                 2 ppm 
                 2 ppm 
               
               
                 [Ta + W + 
                 19.17 
                 19.11 
                 19.13 
               
               
                 Mo + Re] 
               
               
                 [Al + Ti] 
                 6.59 
                 6.54 
                 6.56 
               
               
                 [Al + Ti + Ta] 
                 14.79 
                 14.74 
                 14.76 
               
               
                   
               
             
          
         
       
     
     The creep-rupture properties of the Mod C chemistry (Table 3, 4, 5 and 6) are quite remarkable and surprising for relatively small changes in aim chemistry. The metal temperature stress-rupture capability advantage of Mod C over standard CMSX-4® is 40° F. (22° C.) at 1800° F. (982° C.) and 50° F. (28° C.) for 1.0% creep capability (density corrected). At the 15.0 ksi/2050° F. (103 MPa/1121° C.) very high temperature test condition, the Mod C is equivalent to CMSX-4® which has very exceptional stress-rupture life at this test condition, but with improved rupture ductility (17-28% Elong (4D) and 38-39% RA) compared to CMSX-4®. 
     Remarkably the density corrected creep-rupture properties of Mod C at 36.0 ksi/1800° F. (248 MPa/982° C.) are close to that of CMSX-10K® (6.3% Re) and superior at 15.0 ksi/2050° F. (103 MPa/1121°). (Table 7). 
     The heat treatment used a peak solution/homogenization step of 2435° F. (1335° C.)—(6 hrs) and two (2) differing primary ages (a) 2100° F. (1149° C.)—(6 hrs) and (b) 2125° F. (1163° C.)—(6 hrs)—all test bars for Mod A, B and C were given a final 1600° F.—(20 hrs) age. It is apparent from Table 3 that the 2125° F. (1163° C.) primary age (note the higher Re content of Mod C at 4.8%) gives higher stress-rupture properties at 15.0 ksi/2050° F. (103 MPa/1121° C.) test conditions compared to the 2100° F. (1149° C.) primary age. The properties for both primary age conditions at 36.0 ksi/1800° F. (248 MPa/982° C.) are the same. 
     The single crystal test bar molds were poured at +30° F. (17° C.) over CMSX-4® conditions for the Mod B and C alloys, based on DSC liquidus data. 
     The Mod A and Mod B single crystal test bars were pre-homogenized/partially solutioned with the following initial steps—2395° F. (1313° C.)/2 hrs+2405° F. (1318° C.)/2 hrs+2415° F. (1324° C.)/2 hrs+2425° F. (1329° C.)/2 hrs—prior to the selected 2435° F.). (1335° C.)/6 hrs AC, final peak step. 
     The Mod B single crystal bars ex SMP SX foundry were given an additional 2440° F. (1338° C.)/2 hrs AC peak step to take into account the larger dendrite arm spacing of this mold of test bars. 
     The Mod C single crystal bars were pre-solutioned as above, but with 6 hrs at the 2425° F. (1329° C.) step, prior to the final peak at 2435° F. (1335° C.)/6 hrs AC. 
     CMSX-4® Plus Mod B and Mod C 
     Chemistry Specification Range (Wt % or PPM) 
     Ni-Base Alloy for SX Casting 
                                                                 Hf   0.08-0.15%           C   100 ppm Max    Zr   150 ppm Max            Si   0.04% Max   Cu   0.01% Max           Mn   0.01% Max   Fe   0.15% Max           S    3 ppm Max   V   0.10% Max           P   30 ppm Max   Ru   0.15% Max           B   30 ppm Max   Pt   0.25% Max           Cb   0.15% Max   Pd   0.20% Max           Al   5.60-5.80%   Mg   0.02% Max           Co   9.4-9.8%   [N]   5 ppm Max           Cr   3.2-3.9%   [O]   5 ppm Max           Ta   7.8-8.5%           W   5.3-5.7%           Mo   0.50-0.70%           Re   4.3-4.9%           Ti   0.75-0.90%                        
For single crystal vane segments or large IGT airfoil components, low angle boundary (LAB) strengthened versions would be necessary with: carbon (C) 0.02-0.05% and boron (B) 50-100 ppm.
 
                                                               Mod B   Mod C                                        [Ta + Mo + W + Re]   18.2-19.0   18.7-19.5           [Al + Ti + Ta]   14.25-14.75   14.50-15.0                         
Trace Element Controls:—(PPM)
 
     
       
         
               
               
               
               
               
               
               
               
             
           
               
                   
               
             
             
               
                 Ag 
                  2 Max 
                 Te 
                 0.2 Max     
                 Hg 
                 2 Max 
                 K 
                 10 Max 
               
               
                 Bi 
                 0.2 Max  
                 Tl 
                 0.2 Max     
                 Cd 
                 0.2 Max     
                 Ba 
                 10 Max 
               
               
                 Ga 
                 10 Max 
                 Sn 
                 10 Max  
                 In 
                 0.2 Max     
                 Th 
                  2 Max 
               
               
                 Ca 
                 25 Max 
                 Sb 
                 2 Max 
                 Ge 
                 2 Max 
                 U 
                  2 Max 
               
               
                 Pb 
                  1 Max 
                 As 
                 2 Max 
                 Au 
                 2 Max 
               
               
                 Se 
                 0.5 Max  
                 Zn 
                 5 Max 
                 Na 
                 20 Max  
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 CMSX-4 ® MOD A PLUS HEAT 5V0603 
               
               
                 Heat 5V0603 - Mold 968 - RR (SCO) and Mold 52 J - SMP 
               
               
                 Fully Heat Treated - Solution + double age 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                 Time to 
                 Time to 
                   
                   
                   
                   
                 Time to 
                 Time to 
               
               
                 Test 
                   
                 Rupture 
                 % Elong 
                   
                 1.0% 
                 2.0% 
                   
                 Rupture 
                 % Elong 
                   
                 1.0% 
                 2.0% 
               
               
                 Condition 
                 ID 
                 Life, Hrs 
                 (4D) 
                 % RA 
                 Creep 
                 Creep 
                 SMP ID 
                 Life, Hrs 
                 (4D) 
                 % RA 
                 Creep 
                 Creep 
               
               
                   
               
               
                 1418° F./116.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JFE 
                 120.3 
                 18.9 
                 28.7 
                 1.2 
                 1.7 
               
               
                 [770° C./799 MPa] 
                   
                   
                   
                   
                   
                   
                 52JG0 
                 34.9 
                 32.0 
                 33.5 
                 0.9 
                 1.2 
               
               
                 1562° F./94.4 ksi 
                 A968 
                 182.4 
                 23.7 
                 25.4 
                 1.1 
                 13.6 
                 52JG1 
                 193.6 
                 23.2 
                 27.8 
                 1.0 
                 5.5 
               
               
                 [850° C./651 MPa] 
                 B968 
                 196.2 
                 21.6 
                 27.3 
                 0.6 
                 1.4 
                 52JG2 
                 182.9 
                 24.9 
                 25.6 
                 0.7 
                 2.1 
               
               
                 1600° F./75.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JG3 
                 621.7 
                 24.6 
                 25.1 
                 5.7 
                 68.6 
               
               
                 [871° C./517 MPa] 
                   
                   
                   
                   
                   
                   
                 52JFU 
                 647.6 
                 30.3 
                 31.9 
                 81.2 
                 166.7 
               
               
                 1742° F./56.6 ksi 
                   
                   
                   
                   
                   
                   
                 52JFJ 
                 199.7 
                 32.2 
                 33.6 
                 66.3 
                 103.5 
               
               
                 [950° C./390 MPa] 
                   
                   
                   
                   
                   
                   
                 52JFP 
                 196.9 
                 37.6 
                 38.6 
                 76.7 
                 105.9 
               
               
                 1800° F./32.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JFK 
                 531.2 
                 27.3 
                 42.1 
                 324.2 
                 366.8 
               
               
                 [1010° C./248 MPa] 
                   
                   
                   
                   
                   
                   
                 52JFV 
                 613.2 
                 43.1 
                 43.2 
                 359.0 
                 407.6 
               
               
                 1800° F./36.0 ksi 
                 C968 
                 417.7 
                 43.7 
                 40.4 
                 215.5 
                 249.7 
                 52JFR 
                 370.7 
                 33.8 
                 39.6 
                 210.3 
                 240.6 
               
               
                 [982° C./248 MPa] 
                 D968 
                 379.2 
                 30.9 
                 35.5 
                 202.5 
                 235.7 
                 52JFS 
                 367.2 
                 35.8 
                 38.9 
                 206.2 
                 236.5 
               
               
                 1800° F./40.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JFN 
                 246.9 
                 46.6 
                 39.9 
                 121.6 
                 143.7 
               
               
                 [982° C./276 MPa] 
                   
                   
                   
                   
                   
                   
                 52JFL 
                 202.7 
                 33.9 
                 40.8 
                 101.1 
                 123.6 
               
               
                 1850° F./36.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JFH 
                 124.5 
                 44.8 
                 41.7 
                 66.7 
                 77.0 
               
               
                 [1010° C./248 MPa] 
                   
                   
                   
                   
                   
                   
                 52JFW 
                 153.6 
                 27.3 
                 42.7 
                 80.2 
                 93.5 
               
               
                 1922° F./27.6 ksi 
                 H968 
                 142.8 
                 16.8 
                 36.3 
                 73.2 
                 90.3 
                 52JFF 
                 155.2 
                 17.8 
                 40.2 
                 80.1 
                 99.7 
               
               
                 [1050° C./190 MPa] 
                 K968 
                 144.0 
                 23.7 
                 30.1 
                 66.6 
                 83.9 
                 52JFX 
                 117.7 
                 12.8 
                 38.4 
                 70.4 
                 85.4 
               
               
                 2000° F./18.1 ksi 
                   
                   
                   
                   
                   
                   
                 52JFG 
                 371.9 
                 36.0 
                 37.4 
                 184.6 
                 225.9 
               
               
                 [1093° C./125 MPa] 
                   
                   
                   
                   
                   
                   
                 52JF 
                 353.6 
                 27.5 
                   
                 175.2 
                 221.8 
               
               
                   
               
             
          
           
               
                 Stress-Rupture 
               
             
          
           
               
                   
                   
                 Rupture 
                   
                   
                   
                 Rupture 
                   
                   
               
               
                 Test Condition 
                 ID 
                 Life, hrs 
                 % Elong 
                 % RA 
                 SMP ID 
                 Life, hrs 
                 % Elong 
                 % RA 
               
               
                   
               
               
                 2050° F./15.0 ksi 
                 M968 
                 368.0 
                 8.9 
                 34.9 
                 52JFZ 
                 326.8 
                 9.7 
                 36.7 
               
               
                 [1121°/103 MPa] 
                 N968 
                 370.0 
                 20.1 
                 38.3 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 CMSX-4 ® PLUS MOD B HEAT 5V0636 
               
               
                 Heat 5V0636 - Molds 975 and 977 - RR (SCO and Mold 52 J - SMP 
               
               
                 Fully Heat Treated - Solution + double age 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                 Time to 
                 Time to 
                   
                 Rupture 
                   
                   
                 Time to 
                 Time to 
               
               
                   
                   
                 Rupture 
                 % Elong 
                   
                 1.0% 
                 2.0% 
                 SMP 
                 Life, 
                 % Elong 
                   
                 1.0% 
                 2.0% 
               
               
                 Test Condition 
                 ID 
                 Life, Hrs 
                 (4D) 
                 % RA 
                 Creep 
                 Creep 
                 ID 
                 Hrs 
                 (4D) 
                 % RA 
                 Creep 
                 Creep 
               
               
                   
               
               
                 1562° F./94.4 ksi 
                 B975 
                 223.7 
                 23.3 
                 29.5 
                 0.7 
                 1.6 
                 52JF2 
                 115.7 
                 13.5 
                 28.0 
                 0.6 
                 0.9 
               
               
                 [850° C./651 MPa] 
                 A977 
                 218.7 
                 20.6 
                 28.8 
                 1.0 
                 1.4 
                 52JF7 
                 113.0 
                 18.4 
                 26.2 
                 0.4 
                 0.7 
               
               
                   
                 B977 
                 252.1 
                 17.9 
                 26.4 
                 1.0 
                 2.1 
               
               
                 1600° F./75.0 ksi 
                   
                   
                   
                   
                   
                   
                 52JEU 
                 778.2 
                 18.7 
                 18.8 
                   
                 246.7 
               
               
                 [871° C./517 MPa] 
                   
                   
                   
                   
                   
                   
                 52JT9 
                 859.9 
                 20.3 
                 23.2 
                   
                 198.3 
               
               
                 1742° F./56.6 ksi 
                 C977 
                 222.8 
                 28.2 
                 29.1 
                 95.8 
                 125.1 
                 52JFD 
                 198.1 
                 20.9 
                 31.5 
                 67.9 
                 103.9 
               
               
                 [950° C./390 MPa] 
                 D977 
                 237.0 
                 31.7 
                 33.2 
                 108.3 
                 140.3 
                 52JET 
                 206.8 
                 28.0 
                 30.1 
                 109.0 
                 138.4 
               
               
                 1800° F./36.0 ksi 
                 C975 
                 450.9 
                 28.5 
                 40.2 
                 267.2 
                 300.0 
               
               
                 [982° C./248 MPa] 
                 D975 
                 535.1 
                 29.0 
                 38.3 
                 293.3 
                 339.6 
               
               
                 1800° F./40.0 ksi 
                 E977 
                 268.9 
                 28.1 
                 35.9 
                 157.3 
                 179.6 
                 52JF6 
                 305.8 
                 26.2 
                 31.1 
                 161.2 
                 195.8 
               
               
                 [982° C./276 MPa] 
                 H977 
                 290.8 
                 27.3 
                 37.0 
                 198.9 
                 213.3 
                 52JFA 
                 292.3 
                 35.2 
                 31.8 
                 158.9 
                 185.3 
               
               
                 1850° F./36.0 ksi 
                 E975 
                 179.6 
                 31.0 
                 38.2 
                 89.7 
                 106.6 
                 52JF1 
                 169.7 
                 29.3 
                 37.8 
                 92.6 
                 107.6 
               
               
                 [1010° C./248 MPa] 
                 H975 
                 158.7 
                 31.4 
                 35.6 
                 88.2 
                 101.2 
                 52JEP 
                 163.4 
                 28.8 
                 30.2 
                 94.2 
                 108.6 
               
               
                 1900° F./25.0 ksi 
                 K977 
                 385.6 
                 18.1 
                 37.2 
                 211.1 
                 252.7 
               
               
                 [1038° C./172 MPa] 
                 M977 
                 387.6 
                 23.6 
                 35.8 
                 198.8 
                 239.0 
               
               
                 1922° F./27.6 ksi 
                 J975 
                 154.4 
                 15.1 
                 30.6 
                 62.4 
                 91.2 
                 52JEY 
                 174.6 
                 13.5 
                 31.6 
                 92.1 
                 116.3 
               
               
                 [1050° C./190 MPa] 
                 K975 
                 212.9 
                 18.2 
                 30.2 
                 103.8 
                 129.5 
                 52JE5 
                 162.5 
                 13.6 
                 31.3 
                 85.7 
                 108.2 
               
               
                 2000° F./18.1 ksi 
                 N977 
                 333.7 
                 13.8 
                 34.6 
                 178.3 
                 227.5 
               
               
                 [1093° C./125 MPa] 
                 R977 
                 395.9 
                 18.1 
                 33.0 
                 195.3 
                 245.8 
               
               
                   
               
             
          
           
               
                 Stress-Rupture 
               
             
          
           
               
                   
                   
                   
                 Rupture 
                   
                   
               
               
                   
                 Test Condition 
                 ID 
                 Life, Hrs 
                 % Elong 
                 % RA 
               
               
                   
                   
               
               
                   
                 2050° F./15.0 ksi 
                 N975 
                 495.4 
                 18.1 
                 38.5 
               
               
                   
                 [1121° C./103 MPa] 
                 R975 
                 507.6 
                 13.0 
                 35.9 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
             
           
               
                 TABLE 3 
               
               
                   
               
               
                 CMSX-4 ® PLUS MOD C HEAT 5V0660 
               
               
                 Heat 5V0660 - Molds 978 and 981 - RR SCO - LA12229 (Joliet 0449/CM-421) 
               
               
                 Fully Heat Treated - Solution + double age (2 options) 
               
               
                   
               
             
             
               
                 Creep-Rupture 
               
             
          
           
               
                   
                   
                   
                   
                   
                 Time to 
                 Time to 
               
               
                   
                   
                 Rupture 
                 % Elong 
                   
                 1.0% Creep 
                 2.0% Creep 
               
               
                 Test Condition 
                 ID 
                 Life, hrs 
                 (4D) 
                 % RA 
                 (Hrs) 
                 (Hrs) 
               
               
                   
               
               
                 1675° F./75.0 ksi 
                 B981** 
                 218.7 
                 21.4 
                 30.2 
                 2.4 
                 33.5 
               
               
                 [913° C./248 MPa] 
                 C981** 
                 213.0 
                 16.1 
                 20.1 
                 24.1 
                 69.8 
               
               
                 1800° F./36.0 ksi 
                 B978* 
                 618.1 
                 41.0 
                 37.5 
                 361.7 
                 416.7 
               
               
                 [982° C./248 MPa] 
                 C978* 
                 614.4 
                 37.5 
                 38.2 
                 381.9 
                 422.9 
               
               
                   
                 J978** 
                 611.0 
                 34.7 
                 37.9 
                 379.6 
                 416.3 
               
               
                   
                 K978** 
                 616.4 
                 40.8 
                 36.4 
                 370.9 
                 410.0 
               
               
                 1800° F./43.0 ksi 
                 D981** 
                 278.0 
                 29.1 
                 37.3 
                 168.7 
                 190.0 
               
               
                 [982° C./296 MPa] 
                 E981** 
                 273.8 
                 24.7 
                 36.6 
                 172.5 
                 195.2 
               
               
                 1850° F./36.0 ksi 
                 J981** 
                 249.7 
                 30.2 
                 35.4 
                 140.5 
                 159.5 
               
               
                 [1010° C./248 MPa] 
                 L981** 
                 203.8 
                 24.1 
                 29.9 
                 119.8 
                 135.3 
               
               
                 1922° F./27.6 ksi 
                 L978** 
                 231.2 
                 31.8 
                 40.4 
                 117.7 
                 138.0 
               
               
                 [1050° C./190 MPa] 
               
               
                   
               
             
          
           
               
                 Stress-Rupture 
               
             
          
           
               
                   
                   
                 Rupture 
                   
                   
               
               
                 Test Condition 
                 ID 
                 Life, hrs 
                 % Elong 
                 % RA 
               
               
                   
               
               
                 2050° F./15.0 ksi 
                 E978* 
                 578.1 
                 21.9 
                 33.6 
               
               
                 [1121°/103 MPa] 
                 H978* 
                 575.7 
                 22.9 
                 34.5 
               
               
                   
                 M978** 
                 654.8 
                 16.6 
                 39.4 
               
               
                   
                 N978** 
                 669.7 
                 27.5 
                 37.7 
               
               
                   
               
               
                 *Primary age - 2100° F. (1149° C.)/6 hrs AC 
               
               
                 **Primary age - 2125° F. (1163° C.)/6 hrs AC 
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 CMSX-4 ® Plus (SLS) Alloy 
               
               
                 Currently completing development by CM - initial V-5 400 lb 
               
               
                 (180 kgs) heats 
               
               
                 5V0603 (MOD A) and 5V0636 (MOD B) and 5V0660 (MOD C) 
               
               
                 Stress-Rupture Properties [DL 10s RR Corpn., SMP SX Bars] 
               
               
                 Life (hrs) 
               
             
          
           
               
                   
                 CMSX-4 ® Plus 
                 CMSX- 
                 CMSX ®- 
               
             
          
           
               
                   
                 MOD A 
                 MOD B 
                 MOD C 
                 4 ® 
                 8 
               
               
                   
                   
               
             
          
           
               
                 651 MPa/850° C. 
                 190 hrs 
                 224 hrs 
                   
                 160 hrs  
                 142 hrs 
               
               
                 (94.4 ksi/1562° F.) 
               
               
                 517 MPa/871° C. 
                 635 Hrs 
                 819 hrs 
                   
                 335 hrs  
                 418 hrs 
               
               
                 (75.0 ksi/1600° F.) 
               
               
                 517 MPa/913° C. 
                   
                 128 hrs 
                 216 hrs 
                 52 hrs 
                  67 hrs 
               
               
                 (75.0 ksi/1675° F.) 
               
               
                 390 MPa/950° C. 
                 198 hrs 
                 202 hrs 
                   
                 70 hrs 
                 103 hrs 
               
               
                 (56.6 ksi/1742° F.) 
               
               
                 248 MPa/982° C. 
                 398 hrs 
                 493 hrs 
                 615 hrs 
                 275 hrs  
                 236 hrs 
               
               
                 (36.0 ksi/1800° F.) 
               
               
                 276 MPa/982° C. 
                 225 hrs 
                 299 hrs 
                   
                 141 hrs  
                 144 hrs 
               
               
                 (40.0 ksi/1800° F.) 
               
               
                 296 MPa/982° C. 
                   
                 200 hrs 
                 276 hrs 
                 88 hrs 
                  89 hrs 
               
               
                 (43.0 ksi/1800° F.) 
               
               
                 248 MPa/1010° C. 
                 139 hrs 
                 169 hrs 
                 227 hrs 
                 82 hrs 
                  85 hrs 
               
               
                 (36.0 ksi/1850° F.) 
               
               
                 190 MPa/1050° C. 
                 143 hrs 
                 184 hrs 
                 231 hrs 
                 90 hrs 
                  81 hrs 
               
               
                 (27.6 ksi/1922° F.) 
               
               
                 103 MPa/1121° C. 
                 369 hrs 
                 502 hrs 
                 662 hrs 
                 640 hrs  
                 293 hrs 
               
               
                 (15.0 KSI/2050° F.) 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 CMSX-4 ® Plus (SLS) Alloy 
               
               
                 Currently completing development by CM - initial V-5 400 lb (180 kgs) heats 
               
               
                 5V0603 (MOD A) and 5V0636 (MOD B) and 5V0660 (MOD C) 
               
               
                 Creep Properties [DL 10s RR Corpn., SMP SX Bars] 
               
               
                 Time to 1.0% Creep (hrs) 
               
             
          
           
               
                   
                 CMSX-4 ® Plus 
                   
               
             
          
           
               
                   
                 MOD A 
                 MOD B 
                 MOD C 
                 CMSX-4 ® 
                 CMSX ®-8 
               
               
                   
                   
               
             
          
           
               
                 390 MPa/950° C. 
                 72 hrs 
                 88 hrs 
                   
                 37 hrs 
                 36 hrs 
               
               
                 (56.6 ksi/1742° F.) 
               
               
                 248 MPa/982° C. 
                 209 hrs  
                 280 hrs  
                 374 hrs 
                 125 hrs  
                 116 hrs  
               
               
                 (36.0 ksi/1800° F.) 
               
               
                 276 MPa/982° C. 
                 110 hrs  
                 160 hrs  
                   
                 72 hrs 
                 55 hrs 
               
               
                 (40.0 ksi/1800° F.) 
               
               
                 296 MPa/982° C. 
                   
                 93 hrs 
                 171 hrs 
                 45 hrs 
                 39 hrs 
               
               
                 (43.0 ksi/1800° F.) 
               
               
                 248 MPa/1010° C. 
                 73 hrs 
                 89 hrs 
                 130 hrs 
                 35 hrs 
                 40 hrs 
               
               
                 (36.0 ksi/1850° F.) 
               
               
                 190 MPa/1050° C. 
                 70 hrs 
                 83 hrs 
                 118 hrs 
                 37 hrs 
                 34 hrs 
               
               
                 (27.6 ksi/1922° F.) 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 6 
               
             
             
               
                   
               
               
                 CMSX-4 ® Plus (SLS) Alloy 
               
               
                 Currently completing development by CM - initial V-5 400 lb 
               
               
                 (180 kgs) heats 
               
               
                 5V0603 (MOD A) and 5V0636 (MOD B) and 5V0660 (MOD C) 
               
               
                 Creep Properties [DL 10s RR Corpn., SMP SX Bars] 
               
               
                 Initial Creep Properties 
               
               
                 Time to 2.0% Creep (hrs) 
               
             
          
           
               
                   
                 CMSX-4 ® Plus 
                 CMSX- 
                 CMSX ®- 
               
             
          
           
               
                   
                 MOD A 
                 MOD B 
                 MOD C 
                 4 ® 
                 8 
               
               
                   
                   
               
             
          
           
               
                 390 MPa/950° C. 
                   
                 121 hrs 
                   
                 — 
                 50 hrs 
               
               
                 (56.6 ksi/1742° F.) 
               
               
                 248 MPa/982° C. 
                 243 hrs 
                 320 hrs 
                 416 hrs 
                 160 hrs  
                 136 hrs  
               
               
                 (36.0 ksi/1800° F.) 
               
               
                 276 MPa/982° C. 
                 134 hrs 
                 190 hrs 
                   
                 — 
                 79 hrs 
               
               
                 (40.0 ksi/1800° F.) 
               
               
                 248 MPa/1010° C. 
                  85 hrs 
                 103 hrs 
                 147 hrs 
                 45 hrs 
                 48 hrs 
               
               
                 (36.0 ksi/1850° F.) 
               
               
                 190 MPa/1050° C. 
                  87 hrs 
                 110 hrs 
                 138 hrs 
                 54 hrs 
                 43 hrs 
               
               
                 (27.6 ksi/1922° F.) 
               
               
                   
               
             
          
         
       
     
                                                             TABLE 7                   CMSX-4 ® Plus (SLS) Mod C       The creep-rupture properties of the above alloy are quite       close to that of CMSX-10K ® [6.3% Re] - see       table below (not density corrected).       Based on typical average properties:-                Time to   Time to   Time to           Rupture   1% Creep   2% Creep                        248 MPa/982° C.   CMSX-4 ® Plus   615 hrs   374 hrs   416 hrs       (36.0 ksi/1800° F.)   Mod C (5V0660)           CMSX-10K ®   718 hrs   390 hrs   459 hrs       103 MPa/1121° C.   CMSX-4 ® Plus   662 hrs   NA   NA       (15.0 ksi/2050° F.)   Mod C (5V0660)           CMSX-10K ®   558 hrs   NA   NA                    
The density at room temperature of CMSX-4® Plus Mod B (5V0636) determined by the National Physical Laboratories in the UK is 8.887 kg/dm 3 —see table below for comparison with other SX alloys.
 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                   
                 Density (RT) 
               
               
                   
                 Alloy 
                 kg/dm 3   
               
               
                   
                   
               
             
             
               
                   
                 CMSX-4 ® 
                 8.70 
               
               
                   
                 AM 1 
                 8.59 
               
               
                   
                 PWA 1484 
                 8.95 
               
               
                   
                 SC 180 
                 8.84 
               
               
                   
                 Rene′ N-6 
                 8.97 
               
               
                   
                 CMSX-10K ® 
                 9.05 
               
               
                   
                 CMSX-4 ® Plus 
                 8.89 
               
               
                   
                 Mod B 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 8 
               
             
             
               
                   
               
               
                 CMSX-4 ® PLUS MOD B ALLOY ROOM AND 
               
               
                 ELEVATED TEMPERATURE TENSILE DATA 
               
             
          
           
               
                   
                   
                 Test 
                 0.2% Offset 
                 Ultimate 
                   
                   
               
               
                   
                 Identifi- 
                 Temp., 
                 Yield 
                 Tensile 
                 % 
                 % 
               
               
                   
                 cation 
                 ° F. 
                 Strength, Psi 
                 Strength, Psi 
                 Elong. 
                 RA 
               
               
                   
                   
               
             
          
           
               
                 1. 
                 D78B 
                 70 
                 137,900 
                 137,900 
                 17.5 
                 21.1 
               
               
                 2. 
                 K78M 
                 70 
                 140,800 
                 140,800 
                 15.5 
                 17.1 
               
               
                 3. 
                 D78M 
                 800 
                 139,400 
                 140,100 
                 13.2 
                 16.2 
               
               
                 4. 
                 K78T 
                 800 
                 144,200 
                 152,000 
                 12.3 
                 15.5 
               
               
                 5. 
                 D78T 
                 1000 
                 135,300 
                 146,200 
                 17.5 
                 20.1 
               
               
                 6. 
                 L78B 
                 1000 
                 131,600 
                 137,900 
                 19.8 
                 22.9 
               
               
                 7. 
                 I78B 
                 1100 
                 146,600 
                 160,900 
                 10.2 
                 15.5 
               
               
                 8. 
                 L78M 
                 1100 
                 137,400 
                 141,300 
                 12.6 
                 21.2 
               
               
                 9. 
                 I78M 
                 1200 
                 139,000 
                 159,800 
                 14.5 
                 24.7 
               
               
                 10. 
                 L78T 
                 1200 
                 135,600 
                 145,300 
                 13.6 
                 20.4 
               
               
                 11. 
                 I78T 
                 1400 
                 146,800 
                 178,800 
                 8.9 
                 18.7 
               
               
                 12. 
                 M78B 
                 1400 
                 134,700 
                 153,500 
                 12.6 
                 24.9 
               
               
                 13. 
                 J78B 
                 1600 
                 143,800 
                 155,400 
                 22.6 
                 24.0 
               
               
                 14. 
                 M78M 
                 1600 
                 142,700 
                 155,700 
                 30.6 
                 31.1 
               
               
                 15. 
                 J78M 
                 1700 
                 120,500 
                 138,600 
                 25.9 
                 26.7 
               
               
                 16. 
                 M78T 
                 1700 
                 98,600 
                 98,600 
                 32.7 
                 33.9 
               
               
                   
               
             
          
         
       
     
     The 0.2% offset yield strength (YS) the ultimate tensile strength (UTS), percent elongation at the ultimate tensile strength (% Elong), and percent area reduction at the ultimate tensile strength (% RA) at various temperatures for single crystal casting specimens prepared from The MOD B disclosed alloy is presented in Table 8 and illustrated graphically in  FIGS. 1 and 2 . These data show excellent tensile properties at high temperatures, for strength and ductility. 
       FIGS. 3 and 4  are Larson-Miller stress-rupture diagrams comparing the newly disclosed alloys (CMSX-4® PLUS [MOD B] alloy and CMSX-4® PLUS [MOD C] alloy) with well known commercially available nickel-base superalloys for single crystal casting (CMSX-4® alloy and RENÉ N-5 alloy). The illustrated results indicate that a substantial improvement in stress-rupture life for the disclosed alloys as compared with known alloys that are currently used and recognized as preferred materials for casting turbine components for high-temperature, high stress applications. 
     The optical photographs ( FIGS. 5 and 6 ) of a CMSX-4® PLUS (MOD A) single crystal test bar show no γ/γ′ eutectic phase and no incipient melting after being fully heat treated (i.e., solutioned and double aged). 
     The scanning electron micrographs ( FIGS. 7 and 8 ) of the CMSX-4® PLUS (MOD A) single crystal test bar that was fully heat treated (solutioned and double aged) shows aligned cubic γ′ particles having a mean size of about 0.55 micrometers, indicating an appropriate γ/γ′ mis-match. 
     The optical photographs ( FIGS. 9 and 10 ) of a CMSX-4® PLUS (MOD B) single crystal test bar that was solutioned and primary aged shows very small amount of remnant γ/γ′ eutectic phase and no incipient melting. 
     The scanning electron micrographs ( FIGS. 11 and 12 ) of the CMSX-4® PLUS (MOD B) single crystal test bar that was solutioned and primary aged shows dark, aligned cubic γ′ particles having a mean size of about 0.45, indicating an appropriate γ′ mis-match. 
     The optical photographs ( FIGS. 13 and 14 ) of a CMSX-4® PLUS (MOD C) single crystal test bar that was fully heat treated (solutioned and primary aged for 6 hours at 2125° F. (1163° C.)) show a small amount of remnant γ/γ′ eutectic phase (the white spots), indicating no incipient melting. 
     The scanning electron micrographs ( FIGS. 15 and 16 ) of the CMSX-4® PLUS (MOD C) single crystal test bar that was fully heat treated shows dark, aligned cubic γ′ particles having a mean particle size of about 0.45 micrometers, indicating an appropriate γ/γ′ mis-match. 
     The optical photographs ( FIGS. 17 and 18 ) of a CMSX-4® PLUS (MOD C) single crystal test bar that was fully heat treated (solutioned and primary aged for 6 hours at 2125° F. (1163° C.)), and stress-rupture tested at 15 ksi (103 MPa) and 2050° F. (1121° C.) for 669.7 hours life, shows minimal TCP linear dark etching phase, indicating good alloy phase stability.

Technology Category: 8