GB1562082A - Nickel-base olloys - Google Patents
Nickel-base olloys Download PDFInfo
- Publication number
- GB1562082A GB1562082A GB20476/78A GB2047678A GB1562082A GB 1562082 A GB1562082 A GB 1562082A GB 20476/78 A GB20476/78 A GB 20476/78A GB 2047678 A GB2047678 A GB 2047678A GB 1562082 A GB1562082 A GB 1562082A
- Authority
- GB
- United Kingdom
- Prior art keywords
- alloy
- castability
- gamma prime
- nickel
- range
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 229910045601 alloy Inorganic materials 0.000 claims description 63
- 239000000956 alloy Substances 0.000 claims description 63
- 229910052796 boron Inorganic materials 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 13
- 229910052721 tungsten Inorganic materials 0.000 claims description 13
- 229910052782 aluminium Inorganic materials 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 12
- 229910052715 tantalum Inorganic materials 0.000 claims description 12
- 229910052720 vanadium Inorganic materials 0.000 claims description 12
- 229910052726 zirconium Inorganic materials 0.000 claims description 12
- 229910052735 hafnium Inorganic materials 0.000 claims description 11
- 229910052750 molybdenum Inorganic materials 0.000 claims description 10
- 229910052719 titanium Inorganic materials 0.000 claims description 9
- 238000005266 casting Methods 0.000 claims description 8
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- 229910052702 rhenium Inorganic materials 0.000 claims description 8
- 239000012535 impurity Substances 0.000 claims description 7
- 229910000601 superalloy Inorganic materials 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 4
- 239000010941 cobalt Substances 0.000 claims description 4
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 4
- 230000000694 effects Effects 0.000 description 9
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 8
- 238000007711 solidification Methods 0.000 description 8
- 230000008023 solidification Effects 0.000 description 8
- 238000011156 evaluation Methods 0.000 description 6
- 239000000919 ceramic Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 238000005192 partition Methods 0.000 description 3
- 238000005728 strengthening Methods 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 238000007792 addition Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 230000005496 eutectics Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000001729 Ammonium fumarate Substances 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910001005 Ni3Al Inorganic materials 0.000 description 1
- 239000004283 Sodium sorbate Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000001654 beetroot red Substances 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 210000001787 dendrite Anatomy 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000004316 dimethyl dicarbonate Substances 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000004175 ponceau 4R Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B21/00—Unidirectional solidification of eutectic materials
- C30B21/02—Unidirectional solidification of eutectic materials by normal casting or gradient freezing
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C19/00—Alloys based on nickel or cobalt
- C22C19/03—Alloys based on nickel or cobalt based on nickel
- C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
- C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
- C22C19/056—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 10% but less than 20%
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Description
(54) NICKEL-BASE ALLOYS
(71) We, GENERAL ELECTRIC COMPANY, a corporation organised and existing under the laws of the State of New York, United States of America, of 1 River
Road, Schenectady, 12305, State of New York, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
The present invention relates to a nickel-base alloy and cast article and, more particularly, to such an article having directionally oriented grain structure and an improved combination of castability and mechnical properties, particularly in the transverse direction.
In order to meet the higher alloy casting strength requirements in advanced gas turbine engines, it has been determined that directional orientation of the grain structure of such an article would be required. Such a structure is obtainable through several reported processes generally referred to as directional solidification (D.S.). As compared with conventional casting, directionally solidified alloy articles can provide increased life, improved ductility in the longitudinal direction and a significant improvement in thermal fatigue. However, in attempts to improve the strength of such alloys, problems relating to castability and certain mechanical properties, particularly in a transverse direction, have been recognized.
Although a number of Ni-base superalloys particularly useful in connection with directional solidification have been reported, they have been found to have certain undesirable characteristics for selected high temperature applications under difficult stress conditions. For example, the alloy described in U.S. Patent 3,887,363 - Smashey et al, while exhibiting high strength in the growth direction, was found to be limited in the transverse direction due to grain boundary weakness. Therefore, that alloy was found to be especially applicable and desirable in the form of single crystal articles, but not in the directional solidification casting of complex cored, multiple columnar grained turbine blades for advance jet engines because of excessive grain-boundary cracking. Such turbine blades, after removal of the cores, include complex internal air cooling passages or cavities. Marked improvements in castability were required.
Briefly, one form of the alloy composition associated with the present invention and from which the improved air-cooled cast article is made consists essentially of, by weight, 3 - 10% Cr, 10 - 13% Co, 5 - 6% Al, 5 - 7% Ta, up to 2% Ti, up to 2.5% V, 0.5 - 10% Re, 3 - 7% W, 0.5 - 2% Mo, 0.5 - 2% Hf, 0.01 - 0.15% C, 0.005 - 0.05% B, up to 0.1% Zr, up to 1% Cb, with the balance nickel and incidental impurities, the alloy further characterized by the Co being 11 - 13% when the Al is greater than 5.5% or when the W is at least 5% and the fact that it includes 64 - 68 volume percent gamma prime phase.
For less complex air-cooled articles, the composition consists essentially of, by weight, 4 - 9% Cr, 10 - 13% Co, 5 - 6% Al, 5 - 7% Ta, up to about 2% Ti, up to about 2.5% V, 2 - 6% Re, 3 - 6% W, 0.5 - 2% Mo, about 0.5 - 2% Hf, about 0.01 - 0.1% C, about 0.005 - 0.05% B, up to about 0.1% Zr, up to about 1% Cb, with the balance Ni and incidental impurities, the Co being about 11 - 13% when the Al is greater than about 5.5% or when the W is at least about 5% and the gamma prime being in the range of about 64 - 68 volume percent.
For more complex air-cooled cast articles, such as turbine blades having very complex internal passages, a more specifically preferred alloy composition within the broad range consists essentially of, by weight, 4.5 - 5.5% Cr, 11.5 - 12.5% Co, 5.3 - 5.8% Al, 5.5 6.5% Ta, 1.5 - 2.5% V, 2.5 - 3.5% Re, 4.5 - 5.5% W, 0.5 - 1.5% Mo, 1.0 - 1.7% Hf, 0.04 - 0.08% C, 0.01 - 0.02% B, 0.01 - 0.05% Zr, with the balance essentially nickel and incidental impurities, including a maximum of about 0.1% Ti, the gamma prime being in the range of about 64 - 68 volume percent.
BRIEF DESCRIPTION OF THE DRAWING
Figure 1 is a graphical comparison of stress rupture properties of a preferred form of the present invention (D.S. 392) with articles cast from current production alloys; and
Figure 2 is a graphical presentaion of tensile strength of a preferred form of the present invention (D.S. 392).
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the evaluation of a variety of alloys for use in the manufacture of advanced turbine blades for turbine engines, the problem of decrease in castability with increasing mechanical properties was recognized. In particular, with some of the stronger alloys which had been cast in the directional solidification process, grain boundary cracking was observed. As a result of a number of evaluations, a castability rating system was selected as shown in the following Table I.
TABLE I
CASTABILITY RATINGS
A - No cracks
B - Minor crack at tip, less than 1/2" long or in starter zone
C - One major crack, greater than 1/2" long
D - Two or three cracks
E - Several cracks, more than 3 and less than 8
F - Many cracks - most grain boundaries
The castability test with which such a rating system was associated employed a tubular crucible within which was placed a ceramic tube of smaller diameter, the lower one inch of which was slotted. This ceramic tube was held within the outer crucible by appropriate spacers. The alloy to be tested, in the form of a 7/16" diameter rod, was placed within the ceramic tube and the entire assembly was placed within apparatus capable of conducting directional solidification. Upon melting of the alloy charge rod, the molten charge filled the space between the outer tube or crucible and the cermic tube, solidifying on the ceramic tube during directional solidification. After removal of the ceramic tube with the alloy deposited thereon, observations were made and the ratings were selected in accordance with Table I.
During the evaluation of the present invention, a wide variety of alloy compositions were melted and tested for castability and various mechanical, oxidation and corrosion properties. The following Table II shows the nominal compositions of alloys selected as typical of those melted and tested during the latter part of the program. Table III compares nominal gamma prime (y') content with castability and stress rupture strength. As used herein, the gamma prime content is determined by phase extractions which resulted in improved calculations for the determination of gamma prime using a computer program based on element partition.
TABLE II
NOMINAL COMPOSITION
Wt %: 5 Cr, 0.06 C, 0.015 B, 0.02 - 0.03 Zr,
Balance Ni and Incidental impurities
Calculated
Nominal γ'
Alloy Co Al Ta V Re W Mo Hf Ti (# 1 Vol. %) 341 3.5 5.8 8 2.5 3 3 - 1.1 - 67 381 3.5 5.5 7 2.2 3 3 - 1.5 - 63 383 3.5 5.5 6 2.2 3 3 1 1.5 - 62 385 3.5 5.5 6 2.2 3 4 1 1.5 - 63 386 3.5 5.5 6 2.2 3 5 1 1.5 - 64 391 7 5.5 6 2.2 3 5 1 1.5 - 65 392 10 5.5 6 2.2 3 5 1 1.5 - 66* 394 10 5.8 8 2.5 3 3 - 1.2 - 68 397 8.5 5.5 6 2.2 3 5 1 1.5 - 65 398 8.5 5.5 6 2.2 3 4.5 1 1.5 - 63 399 8.5 5.5 6 2.2 3 5 - 1.5 - 64 423 10 5.5 6 2.2 - 8 1 1.5 - 66 424 10 5.5 6 1.1 3 5 1 1.5 1.1 68 425 10 5.5 6 - 3 5 1 1.5 2.1 70 392A 12 5.5 6 2.2 3 5 1 1.5 - 66 428 10 5.8 6 1.6 3 5 1 1.5 - 66 433 12 5.8 6 1.6 3 5 1 1.5 - 66 434 14 5.8 6 1.6 3 5 1 1.5 - 66 * both phase extraction and calculation TABLE III
STRENGTH AND CASTABILITY DATA
Stress Rupture
D.S. Nom. at 165 F/60 ksi
Alloy Vol. %γ' Castability Life (hrs) Condition 341 67 E 170 as D-S 381 63 A-B 21 as D-S 383 62 B 15 A 385 63 A-B 92 A 386 64 C-D 178 A 391 65 D-E 368 A 392 66 A-B 234 A 394 68 E-F 134 B 397 65 D-E 162 B 398 63 D-E 201 A 399 64 A-B 81 A 423 66 E 112 A 424 68 E 242 A 425 70 D-E 208 A 392A 66 A 200 A, B 428 66 C-D 182 B 433 66 A-B 177 B 434 66 C 194 B
Condition
A - Full solution heat treatment at 2350 F
B - Partial solution heat treatment at 2200 F for hour.
In this group of alloys intended for casting by directional solidification, the grain boundary strengtheners C, B, Zr and Hf were maintained within the range of, by weight, about 1 - 2% Hf, 0.01 - 0.2% C, 0.01 - 0.05% B and up to 0.05% Zr in order to inhibit grain boundary cracking. Specifically selected for that phase of evaluation was the nominal range of about 0.06% C, 0.015% B and 0.03% Zr, with Hf being varied between 1.0 - 1.5%. In such alloy forms, Cr was maintained within the range of 3 - 10%, and more specifically about 5%; Re was maintained within the range of up to 10%, more specifically about 3%.
A comparison of the strength and castability data of Table III shows the critical effect of Co on castability. For example, alloys from 341 through 391 include Co in the range of up to 7 weight percent whereas the other alloys include Co in greater amounts. In the weaker alloys represented by 381, 383, 385 and 399, a higher degree of castability exists. However, when the gamma prime content of such alloys is increased above about 63%, in order to strengthen the alloy as shown by the increased stress rupture life, a significant change occurs in castability. The criticality of Co in the strengthening mechanism of the present invention is shown by a comparison of alloy forms 391, 392 and 392A wherein the only difference in composition is 7% Co in 391, 10% Co in 392 and 12% Co in 392A. Although alloy form 391 is better in stress rupture life, its castability is unacceptable. The unusual and unexpectedly critical range of Co in the present invention is clearly shown through a comparison of alloy forms 428, 433 and 434 in Tables II and III. Through evaluation of the present invention, it was found that castability can be affected by a small change in Al content while keeping the gamma prime content substantially the same, for example through adjustment of the V content. In order to depict the Co sensitivity, the series of alloy forms represented by alloys 428, 433 and 434 used a base including 5.8% Al and 1.6 V while maintaining other elements consistent with alloy 392, including a nominal gamma prime content at about 66 volume percent. As shown by the data of Table III, when the Al content is greater than about 5.5%, the Co must be greater than 10% in order to maintain the type of castability required in complex air-cooled articles such as turbine blades. As shown by those data of Table III a preferred nominal content of Co is about 12%, with 14% Co in alloy 434 resulting in significantly reduced castability. Therefore, the present invention defines the critical cobalt range as being about 11 - 13% when the Al content is greater than about 5.5%.
Such a drastic change in castability from such a small change either in Co or Al was not known to be predictable before the present invention.
In addition, when W in the range of about 5 - 7 wt. % along with 1 wt. % Mo is included, a significantly greater than expected amount of Co is required. For this reason, the alloy composition associated with the present invention specifies that because Mo is included, cobalt in the range of about 11 - 13% is required for improved castability with 5 - 7% W. However, even at the higher levels of Co within the scope of the present invention, the inclusion of large amounts of gamma prime strengthening elements such as Al, Ta and V to produce a gamma prime content of about 68% or greater, results in an alloy of poor castability. This is shown by a comparison of alloys 392 and 394. The element W is included within the range of about 3 - 7 wt. % because at least about 3% is needed for strength and levels greater than about 7% decreases castability below acceptable limits in the presence of about 5 - 7% Ta and also results in an unstable alloy.
A review of some of the data of Tables II and III might lead one to the conclusion that it would be better to eliminate Mo because of its adverse effect on castability.
However, a comparison between alloys 392, 398 and 399 shows the significant effect a small amount of Mo can have on the stress rupture properties of the alloy associated with the present invention. Therefore, the element Mo has been included within the range of 0.5 - 2 wt. % and preferably 0.5 - 1.5% so long as Co is maintained in the range of about 10 - 13%.
The element C is included in the present invention in the range of about 0.02 - 0.15 wt. %. Higher carbon content tends toward formation of excessive "script" type carbides and can reduce fatigue properties. It functions as a grain boundary strengthener and tends to improve castability.
Thus, it can be seen that, in respect to the combination of strength and castability in alloys intended for use in making directionally solidified, columnar grained cast articles which can be prone to cracking due to complex internal cavities, an unusual and unexpected array of criticalities exist. The present invention defines such an improved directionally oriented cast nickel-base superalloy article having an improved combination of castability and mechanical properties as a result of adherence to the alloy composition range associated with the present invention.
Specifically preferred within the scope of the present invention for the above described directionally solidified cast articles of a complex, cored configuration is the nominal composition shown for alloy form 392A which is representative of the preferred range of 4.5 - 5.5% Cr, 11.5 - 12.5% Co, 5.3 - 5.8% Al, 5.5 - 6.5% Ta, 1.5 - 2.5% V, 2.5 - 3.5% Re, 4.5 - 5.5% W, 0.5 - 1.5% Mo, 1.0 - 1.7% Hf, 0.04 - 0.08% C, 0.01 0.02% B, 0.01 - 0.05% Zr with the balance essentially Ni and incidental impurities, the alloy further characterized by the fact that it contains gamma prime within the range of 64 - 68 vol. %.
The improved stress rupture properties of a directionally solidified article with the scope of the present invention is shown in graphical presentation of Figure 1 which compares the present invention with two commercially available alloys used in gas turbine engine production. A first is a directionally solidified article made from an alloy sometimes identified as MAR-M200 + Hf and having a nominal composition, by weight, of 0.15wot, 9% Cr, 10% Co, 12% W, 5% Al, 2% Ti, 1% Cb, 2% Hf, 0.015% B, 0.05% Zr, with the balance essentially Ni; a second is a conventionally cast article of
Rene' 80 alloy having a nominal composition, by weight, of 0.17% C, 14% Cr, 9.5%
Co, 4% Mo, 4% W, 5% Ti, 3% Al, 0.015% B, 0.03% Zr, with the balance essentially
Ni. As is seen from Figure 1, a directionally solidified article from the D.S. alloy 392 associated with the present invention has significantly better stress rupture properties than do such commercial, production alloys in the D.S. and in the conventionally cast (CC) conditions. The presentation of Figure 1 is in the conventional Larsen-Miller parameter form well known and widely used in the art.
Thus, through an unusual and unexpected balance of elements, the present invention in one form provides an alloy capable of being manufactured into a directionally solidified cast article having an unusual combination of casting capability and stress rupture properties. At the same time, it maintains other adequate properties, for example tensile properties, as shown in the graphical presentation of Figure 2. As was indicated above, the elements Hf, C, B and Zr were included within the specified range for their effect on grain boundary properties. For example, C is included to improve grain boundary and transverse properties; B is included to strengthen grain boundaries; Hf is included for its effect on grain boundary solidification and Zr is included because of its effect on grain boundary properties, although its effect is less pronounced that Hf, C and B.
Cobalt has been included in a particularly critical range for its effect on castability in combination with the strengthening elements W and Mo. W, about half of which partitions as a gamma prime former, has a tendency to improve castability and maintain equivalent strength. Conversely, Mo tends to decrease castability, although it helps maintain strength because it, also, partitions about half to form gamma prime. The unusual and unexpected interrelationship between the amounts of W, Mo and Co, discussed in connection with the above Tables II and III, helps provide the unusual characteristics of the present invention.
The element Cb can be included as a partial substitute for Ta up to about 1 wt. % Cb, although the presence of Cb is not preferred because of its tendency to reduce melting temperature more rapidly than Ta.
As described in U.S. Patent 3,887,363 - Smashey et al, the disclosure of which is incorporated herein by reference, Re acts as a solid solution strengthener in the type of
Ni-base superalloy to which the present invention relates. It is included within the range of about 0.5 - 10 wt. % in the present invention.
As was mentioned above, increasing the amount of gamma prime increases strength because gamma prime is the precipitate hardening phase. However, as the gamma prime is increased, the amount of eutectic increases and castability decreases so that the present invention recognizes the criticality of maintaining gamma prime in the range of about 64 - 68 vol. % even though the trend in design of superalloys is to increase the amount of gamma prime to even higher levels. Similarly, many modern superalloys include substantial amounts of Cr for its effect on oxidation resistance. However, the present invention recognizes that, although less than about 3% Cr is too little for adequate oxidation resistance, greater than about 10 wt. % affects stability and tends to decrease strength in the present invention.
The principal gamma prime formers in the alloy are Al, Ta and V, with, at most, very small amounts of Ti. The Al content must be high enough to stabilize the Ni3Al (gamma prime) structure. Additions of Ta, V and Ti substitute for Al and, as a result, strengthen the structure. Ta and V are preferred over Ti because Ti segregates to dendrite ends more so than do Ta and V, leading to the formation of large amounts of eutectic. This results in reduced castability. Substitution of Ti for V in the alloy caused reduction in castability and, at about 2% Ti, a reduction in strength, as shown in the following Table
IV. Therefore, Ti is not a preferred addition. However, if the V content is decreased, up to about 2 wt. % Ti can be tolerated for some applications as less complex cast articles.
Vanadium is limited to about 2.5% in the alloy because larger amounts tend to reduce the oxidation and hot corrosion resistances.
In one evaluation, comparison of stress rupture strength and castability was made for variations of W and Re, in an attempt to eliminate Re, substituting more W. The data of
Table V shows castings of D.S. alloy form 423 with 8 wt. % W and 0% Re to have low stress rupture properties and poor castability as compared with castings of D.S. alloy form 392, preferred within the scope of the present invention.
TABLE IV
Wt. % Stress Rupture Strength
Alloy V Ti Castability at 1800 F/35 ksi - Life (hrs.) 392 2.2 - A-B 130 424 1.1 1.1 E 124 425 - 2.1 D-E 87
TABLE V
Wt. % Vol. % Stress Rupture Strength
Alloy Re W γ' Castability at 1650 F/60 ksi - Life (hrs.) 392 3 5 66 A-B 234 423 - 8 66 E 112
Claims (5)
1. An improved nickel-base superalloy for use in the casting of a directionally solidified article including a complex internal passage, the alloy consisting of, by weight, 3 10% cr, 10 - 13% co, 5 - 6% Al, 5 - 7% Ta, up to 2% Ti, up to 2.5% V, 0.5 - 10% Re, 3 - 7% W, 0.5 - 2% Mo, 0.5 - 2% Hf, 0.01 - 0.15% C, 0.005 - 0.05% B, up to 0.1% Zr, up to 1 % Cb with the balance Ni and incidental impurities, the alloy further characterized by the cobalt being 11 - 13% when the Al is greater than 5.5% or when the W is at least 5% and including 64 - 68 vol. % gamma prime phase.
2. The alloy of claim 1 in which, by weight, the Cr is 4 - 9%, the Re is 2 - 6%, the Wis 3 - 6%and the Cis 0.01 - 0.1%.
3. The alloy of claim 2 which consists of, by weight, 4.5 - 5.5% Cr, 11.5 - 12.5% Co, 5.3 - 5.8% Al, 5.5 - 6.5% Ta, 1.5 - 2.5% V, 2.5 - 3.5% Re, 4.5 - 5.5% W, 0.5 - 1.5%
Mo, 1.0 - 1.7% Hf, 0.04 - 0.08% C, 0.01 - 0.02% B, 0.01 - 0.05% Zr, with the balance
Ni and incidental impurities, the gamma prime content being in the range of 64 - 68 vol.
%.
4. An improved cast nickel-base alloy article having a complex internal passage, a columnar grain structure and improved castability and stress rupture properties as a result of its being made from the alloy composition of claims 1 - 3.
5. A nickel-base superalloy substantially as herein described with reference to any one of the examples.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US05/842,698 US4169742A (en) | 1976-12-16 | 1977-10-17 | Cast nickel-base alloy article |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1562082A true GB1562082A (en) | 1980-03-05 |
Family
ID=25288032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB20476/78A Expired GB1562082A (en) | 1977-10-17 | 1978-05-18 | Nickel-base olloys |
Country Status (5)
Country | Link |
---|---|
JP (1) | JPS5458621A (en) |
DE (1) | DE2830946A1 (en) |
FR (1) | FR2406001A1 (en) |
GB (1) | GB1562082A (en) |
IT (1) | IT7825637A0 (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3234264A1 (en) * | 1981-09-19 | 1983-04-07 | Rolls-Royce Ltd., London | Alloy for casting single crystals |
US4765850A (en) * | 1984-01-10 | 1988-08-23 | Allied-Signal Inc. | Single crystal nickel-base super alloy |
US4935072A (en) * | 1986-05-13 | 1990-06-19 | Allied-Signal, Inc. | Phase stable single crystal materials |
GB2235697A (en) * | 1986-12-30 | 1991-03-13 | Gen Electric | Nickel-base superalloys |
GB2278850A (en) * | 1986-01-02 | 1994-12-14 | United Technologies Corp | Columnar grain superalloy articles |
WO1999067435A1 (en) * | 1998-06-23 | 1999-12-29 | Siemens Aktiengesellschaft | Directionally solidified casting with improved transverse stress rupture strength |
US6410153B1 (en) | 1999-02-22 | 2002-06-25 | Rolls-Royce Plc | Nickel based superalloy |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4222794A (en) * | 1979-07-02 | 1980-09-16 | United Technologies Corporation | Single crystal nickel superalloy |
AU630623B2 (en) * | 1988-10-03 | 1992-11-05 | General Electric Company | An improved article and alloy therefor |
US5069873A (en) * | 1989-08-14 | 1991-12-03 | Cannon-Muskegon Corporation | Low carbon directional solidification alloy |
US5151249A (en) * | 1989-12-29 | 1992-09-29 | General Electric Company | Nickel-based single crystal superalloy and method of making |
JP2905473B1 (en) | 1998-03-02 | 1999-06-14 | 科学技術庁金属材料技術研究所長 | Method for producing Ni-based directionally solidified alloy |
US20100034692A1 (en) * | 2008-08-06 | 2010-02-11 | General Electric Company | Nickel-base superalloy, unidirectional-solidification process therefor, and castings formed therefrom |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1758010A1 (en) * | 1968-03-20 | 1970-12-10 | Dr Dietrich Merz | Heat-resistant alloys with a proportion of rhenium and hafnium |
US3677331A (en) * | 1969-07-14 | 1972-07-18 | Martin Marietta Corp | Casting process for nickel base alloys |
US3711337A (en) * | 1970-12-16 | 1973-01-16 | United Aircraft Corp | Columnar-grained nickel-base superalloy castings |
DE2311998C3 (en) * | 1973-03-10 | 1978-04-06 | Thyssen Industrie Ag, 4300 Essen | Use of a nickel alloy for components with high creep strength |
US3887363A (en) * | 1973-12-18 | 1975-06-03 | Gen Electric | Nickel-base superalloy cast article |
-
1978
- 1978-05-18 GB GB20476/78A patent/GB1562082A/en not_active Expired
- 1978-06-16 JP JP7225578A patent/JPS5458621A/en active Pending
- 1978-07-13 FR FR7820953A patent/FR2406001A1/en active Granted
- 1978-07-13 IT IT7825637A patent/IT7825637A0/en unknown
- 1978-07-14 DE DE19782830946 patent/DE2830946A1/en not_active Withdrawn
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3234264A1 (en) * | 1981-09-19 | 1983-04-07 | Rolls-Royce Ltd., London | Alloy for casting single crystals |
US4765850A (en) * | 1984-01-10 | 1988-08-23 | Allied-Signal Inc. | Single crystal nickel-base super alloy |
GB2278850A (en) * | 1986-01-02 | 1994-12-14 | United Technologies Corp | Columnar grain superalloy articles |
GB2278850B (en) * | 1986-01-02 | 1995-06-28 | United Technologies Corp | Columnar grain superalloy articles |
US4935072A (en) * | 1986-05-13 | 1990-06-19 | Allied-Signal, Inc. | Phase stable single crystal materials |
GB2235697A (en) * | 1986-12-30 | 1991-03-13 | Gen Electric | Nickel-base superalloys |
GB2235697B (en) * | 1986-12-30 | 1991-08-14 | Gen Electric | Improved and property-balanced nickel-base superalloys for producing single crystal articles. |
WO1999067435A1 (en) * | 1998-06-23 | 1999-12-29 | Siemens Aktiengesellschaft | Directionally solidified casting with improved transverse stress rupture strength |
US6410153B1 (en) | 1999-02-22 | 2002-06-25 | Rolls-Royce Plc | Nickel based superalloy |
Also Published As
Publication number | Publication date |
---|---|
FR2406001B1 (en) | 1981-02-13 |
FR2406001A1 (en) | 1979-05-11 |
JPS5458621A (en) | 1979-05-11 |
IT7825637A0 (en) | 1978-07-13 |
DE2830946A1 (en) | 1979-04-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4169742A (en) | Cast nickel-base alloy article | |
US4222794A (en) | Single crystal nickel superalloy | |
US5540790A (en) | Single crystal nickel-based superalloy | |
EP0246082B1 (en) | Single crystal super alloy materials | |
US5173255A (en) | Cast columnar grain hollow nickel base alloy articles and alloy and heat treatment for making | |
EP0913506B1 (en) | Nickel-based single crystal alloy and a method of manufacturing the same | |
US4853044A (en) | Alloy suitable for making single crystal castings | |
US7473326B2 (en) | Ni-base directionally solidified superalloy and Ni-base single crystal superalloy | |
GB1562082A (en) | Nickel-base olloys | |
JPH0323613B2 (en) | ||
US5338379A (en) | Tantalum-containing superalloys | |
US4288247A (en) | Nickel-base superalloys | |
US20100047110A1 (en) | Ni-base superalloy and gas turbine component using the same | |
US5925198A (en) | Nickel-based superalloy | |
JP3084764B2 (en) | Method for manufacturing Ni-based superalloy member | |
US20050139295A1 (en) | Method for selecting a reduced-tantalum superalloy composition of matter and article made therefrom | |
EP0362661B1 (en) | Cast columnar grain hollow nickel base alloy article and alloy and heat treatment for making | |
US4707192A (en) | Nickel-base single crystal superalloy and process for production thereof | |
US5489346A (en) | Hot corrosion resistant single crystal nickel-based superalloys | |
US5330711A (en) | Nickel base alloys for castings | |
JP3012652B2 (en) | Improved, balanced nickel-based superalloys for producing single crystal products | |
US6224695B1 (en) | Ni-base directionally solidified alloy casting manufacturing method | |
US3314784A (en) | Cobalt-base alloy resistant to thermal shock | |
US3854941A (en) | High temperature alloy | |
GB2401113A (en) | Nickel-based superalloy |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |