CA1284592C - Weldable cast nickel base superalloy - Google Patents
Weldable cast nickel base superalloyInfo
- Publication number
- CA1284592C CA1284592C CA000523849A CA523849A CA1284592C CA 1284592 C CA1284592 C CA 1284592C CA 000523849 A CA000523849 A CA 000523849A CA 523849 A CA523849 A CA 523849A CA 1284592 C CA1284592 C CA 1284592C
- Authority
- CA
- Canada
- Prior art keywords
- waspaloy
- alloy
- weldability
- max
- weldable
- 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 - Lifetime
Links
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 title claims abstract description 16
- 229910000601 superalloy Inorganic materials 0.000 title claims abstract description 9
- 229910052759 nickel Inorganic materials 0.000 title claims abstract description 8
- 229910052742 iron Inorganic materials 0.000 claims abstract description 25
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 15
- 239000000956 alloy Substances 0.000 claims abstract description 15
- 238000005266 casting Methods 0.000 claims abstract description 9
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 9
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 8
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 7
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 7
- 239000011733 molybdenum Substances 0.000 claims abstract description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 6
- 239000011593 sulfur Substances 0.000 claims abstract description 6
- 229910052797 bismuth Inorganic materials 0.000 claims abstract description 5
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000000203 mixture Substances 0.000 claims description 16
- 229910052796 boron Inorganic materials 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims description 2
- 229910052804 chromium Inorganic materials 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 49
- 229910001247 waspaloy Inorganic materials 0.000 abstract description 27
- 239000000463 material Substances 0.000 abstract description 20
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 abstract description 8
- 229910052726 zirconium Inorganic materials 0.000 abstract description 8
- 239000011572 manganese Substances 0.000 abstract description 7
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 abstract description 6
- 238000005275 alloying Methods 0.000 abstract description 3
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- 238000007792 addition Methods 0.000 description 4
- 238000003466 welding Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000003754 machining Methods 0.000 description 3
- 239000011651 chromium Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical group [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical class [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- VCTOKJRTAUILIH-UHFFFAOYSA-N manganese(2+);sulfide Chemical class [S-2].[Mn+2] VCTOKJRTAUILIH-UHFFFAOYSA-N 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- WWNBZGLDODTKEM-UHFFFAOYSA-N sulfanylidenenickel Chemical compound [Ni]=S WWNBZGLDODTKEM-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
-
- 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
- C22C19/055—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 20% but less than 30%
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
- Coating By Spraying Or Casting (AREA)
- Connection Of Batteries Or Terminals (AREA)
- Adornments (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Abstract of the Disclosure Weldable Cast Nickel Base Superalloy Nickel base superalloys of the type referred to as Waspaloy are rendered weldable by limiting the iron content to about one twentieth of that which is commonly present, adding small amounts of manganese to the alloy and removing the zirconium which is commonly present. In addition, the sulfur, bismuth and lead levels are held to the lowest possible limits, and preferably the aluminum and molybdenum are maintained in the lower half of their normal range. By implementing these alloying strategies, the weldability of the cast material is dramatically improved and for the first time castings of the Waspaloy materials are rendered consistently weldable on a commercial scale.
Description
i284592 Description Weldable Cast Nickel Base Superalloy Technical Field The invention relates to the compositional modification of a particular superalloy, known as Waspaloy, to render it weldable.
Background Art The alloy on which this invention is based is referred to as Waspaloy, an alloy developed in the early 1950's for application in gas turbine engines.
The nominal composition of the required elements, by weight, is 19.5% chromium, 13.5% cobalt, 3.75%
molybdenum, 3.0% titanium, 1.12% aluminum, 0.005%
boron, 0.006% carbon, balance nickel. In addition, certain impurities may be present in limited amounts.
The most prominent of these is iron which is permitted in amounts of up to 2 wt.~ (Some early references suggest that iron was a required Waspaloy constituent in an amount of about 3%).
Nickel, the "balance" element in Waspaloy typically costs several dollars per pound. Iron, on the other hand, costs much less than one dollar per pound. Thus, there is an economic incentive for the producers of Waspaloy to add iron so as to reduce their raw material cost. An additional incentive is the fact that much superalloy scrap is contaminated with iron which is a difficult element to remove from such scrap. The availability of such iron rich scrap makes the inclusion of iron in Waspaloy even more likely.
The iron content of 13 heats of Waspaloy material recently received by the assignee of the present invention were analyzed. The average iron content was 1.16% and the minimum iron content was 0.70~. These data support the previously set out thesis that iron will be present in amounts of greater than about 1% in almost any commercial Waspaloy material.
Waspaloy has found widespread application in the gas turbine industry, mostly in wrought and occasionally in cast form. Waspaloy is stronger, especially in the 1000F-1500F range than most alternative compositions.
In the past, the alloy has been used either in wrought form, in which case it can be bent or otherwise ormed into useful shapes or in cast form in which case the essential geometry of the part is established by the casting process. The achievement of intricate shapes and close tolerance dimensions in both wrought and cast parts can also be accomplished by machining. Modern gas turbine engines contain parts of substantial complexity. In addition, there is a great impetus to reduce the weight of engines so that whereas in past engines excessive material in castings was tolerated, in present engines the desire is to remove all excess material. Concurrently there have been great advances in the casting art so that parts of increasing complexity can now be cast in almost the final or net shape and require minimum ~2845~
finish machining. At the same time there has also been an increase both in use temperature and applied stresses so that the driving force has been to go to stronger materials. All of these factors lead the gas turbine engine designer to seek to use complex cast parts of a composition such as Waspaloy. The major problem which is encountered in making such parts is that the alloy is somewhat prone to crack during the casting process. As a result the casting of Waspaloy to date has provided a relatively low yield of crack-free parts. Accordingly, the practical application of cast parts of the Waspaloy composition i5 dependent upon the ability to weld repair castings which exhibit minor cracks and similar defects. It would also be useful to have the capability to repair minor machining flaws in non-critical portions of components by building up material using a welding process when the material has been inadvertently and excessively removed. The Waspaloy composition, however desirable in other respects, has historically suffered from the lack of weldability.
The Waspaloy type composition is described in many U.S. patents, apparently starting from U.S.
Patent No. 2,570,193 filed in 1946 extending through the present day. A partial list of these patents is presented below:
Background Art The alloy on which this invention is based is referred to as Waspaloy, an alloy developed in the early 1950's for application in gas turbine engines.
The nominal composition of the required elements, by weight, is 19.5% chromium, 13.5% cobalt, 3.75%
molybdenum, 3.0% titanium, 1.12% aluminum, 0.005%
boron, 0.006% carbon, balance nickel. In addition, certain impurities may be present in limited amounts.
The most prominent of these is iron which is permitted in amounts of up to 2 wt.~ (Some early references suggest that iron was a required Waspaloy constituent in an amount of about 3%).
Nickel, the "balance" element in Waspaloy typically costs several dollars per pound. Iron, on the other hand, costs much less than one dollar per pound. Thus, there is an economic incentive for the producers of Waspaloy to add iron so as to reduce their raw material cost. An additional incentive is the fact that much superalloy scrap is contaminated with iron which is a difficult element to remove from such scrap. The availability of such iron rich scrap makes the inclusion of iron in Waspaloy even more likely.
The iron content of 13 heats of Waspaloy material recently received by the assignee of the present invention were analyzed. The average iron content was 1.16% and the minimum iron content was 0.70~. These data support the previously set out thesis that iron will be present in amounts of greater than about 1% in almost any commercial Waspaloy material.
Waspaloy has found widespread application in the gas turbine industry, mostly in wrought and occasionally in cast form. Waspaloy is stronger, especially in the 1000F-1500F range than most alternative compositions.
In the past, the alloy has been used either in wrought form, in which case it can be bent or otherwise ormed into useful shapes or in cast form in which case the essential geometry of the part is established by the casting process. The achievement of intricate shapes and close tolerance dimensions in both wrought and cast parts can also be accomplished by machining. Modern gas turbine engines contain parts of substantial complexity. In addition, there is a great impetus to reduce the weight of engines so that whereas in past engines excessive material in castings was tolerated, in present engines the desire is to remove all excess material. Concurrently there have been great advances in the casting art so that parts of increasing complexity can now be cast in almost the final or net shape and require minimum ~2845~
finish machining. At the same time there has also been an increase both in use temperature and applied stresses so that the driving force has been to go to stronger materials. All of these factors lead the gas turbine engine designer to seek to use complex cast parts of a composition such as Waspaloy. The major problem which is encountered in making such parts is that the alloy is somewhat prone to crack during the casting process. As a result the casting of Waspaloy to date has provided a relatively low yield of crack-free parts. Accordingly, the practical application of cast parts of the Waspaloy composition i5 dependent upon the ability to weld repair castings which exhibit minor cracks and similar defects. It would also be useful to have the capability to repair minor machining flaws in non-critical portions of components by building up material using a welding process when the material has been inadvertently and excessively removed. The Waspaloy composition, however desirable in other respects, has historically suffered from the lack of weldability.
The Waspaloy type composition is described in many U.S. patents, apparently starting from U.S.
Patent No. 2,570,193 filed in 1946 extending through the present day. A partial list of these patents is presented below:
2,570,193; 2,977,222; 3,166,412; 3,207,599; 3,512,963;
3,625,678; 3,723,107; 3,850,624; 4,110,110; 4,213,026 and 4,456,481.
128~;9~
In view of the substantial number of issued U.S.
patents in this limited alloy area, it is not surprising that many elements have been added to and/or removed from the basic composition to achieve various purposes. In particular, U.S. Patent No.
3,166,412 deals with a casting made from a Waspaloy type composition and states, in part, that iron is an undesirable element in the alloy and it should not be present in amounts exceeding 0.5% and preferably not greater than 0.25% The nature of the problems resulting from the presence of iron and/or the benefits achieved by limiting iron to these ranges is not set forth. The patent makes no reference to welding or weldability.
Similarly, certain patents teach the addition of manganese in superalloys for purposes relating to improving weldability, for example, U.S. Patent No.
128~;9~
In view of the substantial number of issued U.S.
patents in this limited alloy area, it is not surprising that many elements have been added to and/or removed from the basic composition to achieve various purposes. In particular, U.S. Patent No.
3,166,412 deals with a casting made from a Waspaloy type composition and states, in part, that iron is an undesirable element in the alloy and it should not be present in amounts exceeding 0.5% and preferably not greater than 0.25% The nature of the problems resulting from the presence of iron and/or the benefits achieved by limiting iron to these ranges is not set forth. The patent makes no reference to welding or weldability.
Similarly, certain patents teach the addition of manganese in superalloys for purposes relating to improving weldability, for example, U.S. Patent No.
4,213,026 suggests the addition of 0.5%-3% manganese to nickel base superalloy weld wires for the purpose r of improving the welding process and limiting the incidence of cracking in the heat-affected zone.
However, figures 2 and 3 in the patent and table 4 suggest Waspaloy, even when modified with manganese, remains a marginal candidate for welding.
Summary of Invention Waspaloy type compositions are modified and rendered weldable in cast form by restricting the iron content, which is invariably high in commerical compositions, to less than about 0.2% and preferably less than 0.1%, adding from 0.3%-0.5~ manganese, b '~6 15:~8 UTC ~HTEI~ ~IR~TFOI~ CTSi~l~lS.C;55 p,~3 ~8459~
limiting the zirconium content, limiting sul~r, bi~muth and lead to be a~ low as possible, and preferably maintainin~ alu~lnum and molybdenum at the low end of the normal ~aspaloy compositlon range.
~he foregoing ~nd other feat~re~ and advantages of the present lnventlon will become more apparent from the following description.
aest Mode for Carrying ~ut the Inventlon ~he commercial specification for ~a~paloy permits the presence of up to ~% iron. Al~hough lron i~
allowed in variou~ su~erAlloy~, especially earller developed superfllloys, the Wsspaloy composltion is un~sual among ~uperalloy~ in si~niflcant contemporary usage in permitting iron in thi~ level.
we have fo~nd ~hat the pre~ence of lron in more than ~bout 0.2% by ~ei~ht ln the Waspaloy composition has a dramatic e~fect on the weld~bllit~ of such material, Table 1 preQentOE the compo~ition of a varlety of cast Waspal4y component~ ~hich have been ~0 weld repaired at the facillties of the aa~ignee of the present invention. Composltions 1 throu~h 6 were found to be es~entially unweldable ~hile compo~itions 7 through 12, which were ~ormulated iQ accordance with the present invention, were found to be rellably weldable. Weldabillty wa~ a~seesed by evaluating weld made with GTA ~elding equipment for cracklng and other defects. The most notable distinction between the weldable and the nonweldflble compositlons i$ the iron content. It can b~ seen that the weldable compositi4n~ all contain le~s than 0.2~ iron, while 12~34~9Z
the unweldable compositions were all commercially obtained heats of materials which contained more than 1 wt.% iron. Accordingly, a primary aspect of the present invention is the discovery that the weldability of Waspaloy type material can be dramatically improved through the limitation of iron to less than 0.2% and preferably less than 0.1% by weight.
Preferably in addition to limiting the iron content, intentional additions of manganese in amounts of 0.3%-0.5% by weight are made. In addition, we prefer to limit the zirconium content to less than 0.02% by weight and preferably we prefer to make no intentional zirconium additions at all. Zirconium has historically been added to Waspaloy in the belief that it improved the stress rupture properties, however extensive testing has failed to show any difference in stress rupture properties between Waspaloy materials containing conventional amounts of zirconium and those containing no intentional zirconium.
In addition, there are certain elements which are generally regarded in the prior art as being detrimental to weldability including sulfur, bismuth and lead. Such elements are known to segregate to the grain boundaries and are either inherently low melting materials or form low melting phases in grain boundaries thereby causing substantial cracking.
Sulfur forms low melting point nickel sulfide phases.
While the previously mentioned manganese reduces the effect of sulfur by forming manganese sulfides at the grain boundaries which have substantially higher 128~592 melting point than the iron sulfides which would otherwise form, it is nonetheless desirable to limit the sulfur content to be as low as possible.
Additionally, the bismuth and lead are inherently low melting point materials which segregate to grain boundaries, so it is also desirable to limit these materials to as low levels as possible. Control of the amounts of these elements can be achieved by formulating the alloy from virgin material (i.e. pure forms of the alloying elements) rather than using scrap or revert material.
A final alloying modification which can be made to improve the weldability of the material is to limit the aluminum and molybdenum contents to approximately the lower half of the normal range for these elements in the Waspaloy specification. We have found that even though aluminum and molybdenum are both strengthening elements, limiting these elements to the lower half of their normal range (e.g. 1-1.125% Al and 20 3.5-4.25% Mo) does not significantly affect strength, but does appear to improve weldability. Consequently in the most preferred form of the present invention these elements are limited to the lower half of their normal range. Table 2 presents the nominal composition for conventional (cast) Waspaloy material, and the composition range for the present invention.
The composition range for the present invention is that of the invention in its most preferred and limited form. We believe that the order of benefit obtained according to the present invention is that limiting the iron is the most significant factor in ~;~B~;~
improving weldability, that adding manganese is the next most significant factor, that removing the zirconium is the third significant factor, that limiting sulfur, bismuth and lead is the fourth significant factor and that the fifth significant factor is limiting the aluminum and molybdenum to the lower end of their normal ranges.
Although this invention has been shown and described with respect to detailed embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail thereof may be made without departing from the spirit and scope of the claimed invention.
~ I o _ o o o o ~, V V V V V V V V
I ~ ~ 3) ~ cn ~ o o o o -- o I _ _ _ o _ _ ~ o o C~ o o o ~ _ ~
S~ g O O O _ CD I O O O O O O
o o o o o o , o o o o o o o _ _ o _~ _ _ _ o o :~ O~ r` Q Q
~n I I o o O O O 0 11 ~ O O O O O O
. ~ ~ r OOr _ I O O O ~0 0 0 I o o o o o o I o o o o o o C u- ~ _ o o~ ~ ~ ~r ~ ~ ~r . o o _ o oo I o o o o o o 'z ~
Z O O O O ~ O O O O O O
I v v m I I O O 0O 0 0 ~0 O O O O a 4 . I O O O o O ,0 3 _ ~ _ _ ~ _ _ _ ~ It~ ~ ~ 0 N ~ ~
O O O O . I O O O O O O
C,~ O O O O -- 1- 1 0 0 0 0 0 0 ~ ~ ~ O _ _ 9 _ 128~592 TABLE II
MOST
STANDARD BROAD PREFERRED PREFERRED
WASPALOY RANGE RANGE RANGE
Cr 18-21 18-21 18-21 18-21 Co 12-15 12-15 12-15 12-15 Ti 2.75-3.25 2.75-3.25 2.75-3.25 2.75-3.25 B 0.002-0.008 0.002-0.008 0.002-0.008 0.002-0.008 C 0.03-0.1 0.03-0.1 0.03-0.1 0.03-0.1 Cu 0.1 max 0.1 max 0.1 max 0.1 max P 0.015 0.015 0.015 0.015 Se 0.5ppm max 0.Sppm max 0.5ppm max 0.5ppm max Te 0.2ppm max 0.2ppm max 0.2ppm max 0.2ppm max Th 0.2ppm max 0.2ppm max 0.2ppm max 0.2ppm max Fe 2.0 max 0.2 max 0.1 max 0.1 max Mn 0.5 max 0.3-0.5 0.3-0.5 0.3-0.5 Zr 0.12 max n.l2 max 0.02 max 0.02 max S 0.03 max 0.03 max 0.005 max 0.005 max Al 1.0-1.5 1.0-1.5 1.0-1.5 1.0-1.125 Mo 3.5-5.0 3.5-5.0 3.5-5.0 3.5-4.25 Ni Bal Bal Bal Bal
However, figures 2 and 3 in the patent and table 4 suggest Waspaloy, even when modified with manganese, remains a marginal candidate for welding.
Summary of Invention Waspaloy type compositions are modified and rendered weldable in cast form by restricting the iron content, which is invariably high in commerical compositions, to less than about 0.2% and preferably less than 0.1%, adding from 0.3%-0.5~ manganese, b '~6 15:~8 UTC ~HTEI~ ~IR~TFOI~ CTSi~l~lS.C;55 p,~3 ~8459~
limiting the zirconium content, limiting sul~r, bi~muth and lead to be a~ low as possible, and preferably maintainin~ alu~lnum and molybdenum at the low end of the normal ~aspaloy compositlon range.
~he foregoing ~nd other feat~re~ and advantages of the present lnventlon will become more apparent from the following description.
aest Mode for Carrying ~ut the Inventlon ~he commercial specification for ~a~paloy permits the presence of up to ~% iron. Al~hough lron i~
allowed in variou~ su~erAlloy~, especially earller developed superfllloys, the Wsspaloy composltion is un~sual among ~uperalloy~ in si~niflcant contemporary usage in permitting iron in thi~ level.
we have fo~nd ~hat the pre~ence of lron in more than ~bout 0.2% by ~ei~ht ln the Waspaloy composition has a dramatic e~fect on the weld~bllit~ of such material, Table 1 preQentOE the compo~ition of a varlety of cast Waspal4y component~ ~hich have been ~0 weld repaired at the facillties of the aa~ignee of the present invention. Composltions 1 throu~h 6 were found to be es~entially unweldable ~hile compo~itions 7 through 12, which were ~ormulated iQ accordance with the present invention, were found to be rellably weldable. Weldabillty wa~ a~seesed by evaluating weld made with GTA ~elding equipment for cracklng and other defects. The most notable distinction between the weldable and the nonweldflble compositlons i$ the iron content. It can b~ seen that the weldable compositi4n~ all contain le~s than 0.2~ iron, while 12~34~9Z
the unweldable compositions were all commercially obtained heats of materials which contained more than 1 wt.% iron. Accordingly, a primary aspect of the present invention is the discovery that the weldability of Waspaloy type material can be dramatically improved through the limitation of iron to less than 0.2% and preferably less than 0.1% by weight.
Preferably in addition to limiting the iron content, intentional additions of manganese in amounts of 0.3%-0.5% by weight are made. In addition, we prefer to limit the zirconium content to less than 0.02% by weight and preferably we prefer to make no intentional zirconium additions at all. Zirconium has historically been added to Waspaloy in the belief that it improved the stress rupture properties, however extensive testing has failed to show any difference in stress rupture properties between Waspaloy materials containing conventional amounts of zirconium and those containing no intentional zirconium.
In addition, there are certain elements which are generally regarded in the prior art as being detrimental to weldability including sulfur, bismuth and lead. Such elements are known to segregate to the grain boundaries and are either inherently low melting materials or form low melting phases in grain boundaries thereby causing substantial cracking.
Sulfur forms low melting point nickel sulfide phases.
While the previously mentioned manganese reduces the effect of sulfur by forming manganese sulfides at the grain boundaries which have substantially higher 128~592 melting point than the iron sulfides which would otherwise form, it is nonetheless desirable to limit the sulfur content to be as low as possible.
Additionally, the bismuth and lead are inherently low melting point materials which segregate to grain boundaries, so it is also desirable to limit these materials to as low levels as possible. Control of the amounts of these elements can be achieved by formulating the alloy from virgin material (i.e. pure forms of the alloying elements) rather than using scrap or revert material.
A final alloying modification which can be made to improve the weldability of the material is to limit the aluminum and molybdenum contents to approximately the lower half of the normal range for these elements in the Waspaloy specification. We have found that even though aluminum and molybdenum are both strengthening elements, limiting these elements to the lower half of their normal range (e.g. 1-1.125% Al and 20 3.5-4.25% Mo) does not significantly affect strength, but does appear to improve weldability. Consequently in the most preferred form of the present invention these elements are limited to the lower half of their normal range. Table 2 presents the nominal composition for conventional (cast) Waspaloy material, and the composition range for the present invention.
The composition range for the present invention is that of the invention in its most preferred and limited form. We believe that the order of benefit obtained according to the present invention is that limiting the iron is the most significant factor in ~;~B~;~
improving weldability, that adding manganese is the next most significant factor, that removing the zirconium is the third significant factor, that limiting sulfur, bismuth and lead is the fourth significant factor and that the fifth significant factor is limiting the aluminum and molybdenum to the lower end of their normal ranges.
Although this invention has been shown and described with respect to detailed embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail thereof may be made without departing from the spirit and scope of the claimed invention.
~ I o _ o o o o ~, V V V V V V V V
I ~ ~ 3) ~ cn ~ o o o o -- o I _ _ _ o _ _ ~ o o C~ o o o ~ _ ~
S~ g O O O _ CD I O O O O O O
o o o o o o , o o o o o o o _ _ o _~ _ _ _ o o :~ O~ r` Q Q
~n I I o o O O O 0 11 ~ O O O O O O
. ~ ~ r OOr _ I O O O ~0 0 0 I o o o o o o I o o o o o o C u- ~ _ o o~ ~ ~ ~r ~ ~ ~r . o o _ o oo I o o o o o o 'z ~
Z O O O O ~ O O O O O O
I v v m I I O O 0O 0 0 ~0 O O O O a 4 . I O O O o O ,0 3 _ ~ _ _ ~ _ _ _ ~ It~ ~ ~ 0 N ~ ~
O O O O . I O O O O O O
C,~ O O O O -- 1- 1 0 0 0 0 0 0 ~ ~ ~ O _ _ 9 _ 128~592 TABLE II
MOST
STANDARD BROAD PREFERRED PREFERRED
WASPALOY RANGE RANGE RANGE
Cr 18-21 18-21 18-21 18-21 Co 12-15 12-15 12-15 12-15 Ti 2.75-3.25 2.75-3.25 2.75-3.25 2.75-3.25 B 0.002-0.008 0.002-0.008 0.002-0.008 0.002-0.008 C 0.03-0.1 0.03-0.1 0.03-0.1 0.03-0.1 Cu 0.1 max 0.1 max 0.1 max 0.1 max P 0.015 0.015 0.015 0.015 Se 0.5ppm max 0.Sppm max 0.5ppm max 0.5ppm max Te 0.2ppm max 0.2ppm max 0.2ppm max 0.2ppm max Th 0.2ppm max 0.2ppm max 0.2ppm max 0.2ppm max Fe 2.0 max 0.2 max 0.1 max 0.1 max Mn 0.5 max 0.3-0.5 0.3-0.5 0.3-0.5 Zr 0.12 max n.l2 max 0.02 max 0.02 max S 0.03 max 0.03 max 0.005 max 0.005 max Al 1.0-1.5 1.0-1.5 1.0-1.5 1.0-1.125 Mo 3.5-5.0 3.5-5.0 3.5-5.0 3.5-4.25 Ni Bal Bal Bal Bal
Claims (5)
1. In a nickel base superalloy having a nominal composition of 19.5% Cr, 13.5% Co, 3.75% Mo, 3.0% Ti, 1.12% Al, 0.005% B, 0.006% C and containing up to 2.0%
Fe, the improvement which comprises limiting the Fe level to not more than 0.2%, whereby the weldability of castings made of the alloy is substantially increased.
Fe, the improvement which comprises limiting the Fe level to not more than 0.2%, whereby the weldability of castings made of the alloy is substantially increased.
2. In an alloy as in claim 1, the further improvement which comprises adding from 0.3% to 0.5% Mn to the alloy, whereby the weldability is further increased.
3. In an alloy as in claim 2, the further improvement which comprises making no intentional addition of Zr and limiting the Zr content to not more than 0.02%, whereby still further improvements in weldability result.
4. In an alloy as in claim 3 the further improvement which comprises limiting the levels of sulfur, bismuth and lead to low levels by formulating the alloy from virgin stock, whereby further enhancement of weldability will result.
5. In an alloy as in claim 4 the further improvement which comprises limiting the aluminum content to 1.0%-1.125% and limiting the molybdenum content to 3.5%-4.25% whereby still further improvements in weldability will result.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US80198385A | 1985-11-26 | 1985-11-26 | |
| US801,983 | 1985-11-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1284592C true CA1284592C (en) | 1991-06-04 |
Family
ID=25182527
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000523849A Expired - Lifetime CA1284592C (en) | 1985-11-26 | 1986-11-26 | Weldable cast nickel base superalloy |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS62167835A (en) |
| KR (1) | KR930004478B1 (en) |
| CN (1) | CN86107041A (en) |
| AU (1) | AU591198B2 (en) |
| CA (1) | CA1284592C (en) |
| CH (1) | CH677497A5 (en) |
| DE (1) | DE3638855A1 (en) |
| FR (1) | FR2592062B1 (en) |
| GB (1) | GB2183675A (en) |
| IL (1) | IL80732A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2733630B1 (en) * | 1995-04-27 | 1997-05-30 | Imphy Sa | CONNECTING LEGS FOR ELECTRONIC COMPONENT |
| JP5201708B2 (en) * | 2006-04-14 | 2013-06-05 | 三菱マテリアル株式会社 | Ni-based heat-resistant alloy welding wire |
| JPWO2017029856A1 (en) * | 2015-08-18 | 2018-08-09 | 国立研究開発法人物質・材料研究機構 | Recycling method for Ni-base superalloy parts |
| CN105624471A (en) * | 2015-12-21 | 2016-06-01 | 常熟市梅李合金材料有限公司 | Nickel chrome wire |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2570193A (en) * | 1946-04-09 | 1951-10-09 | Int Nickel Co | High-temperature alloys and articles |
| GB919709A (en) * | 1960-03-15 | 1963-02-27 | Mond Nickel Co Ltd | Improvements in nickel-chromium-cobalt alloys |
| US3166412A (en) * | 1962-08-31 | 1965-01-19 | Int Nickel Co | Cast nickel-base alloy for gas turbine rotors |
| US3707409A (en) * | 1970-07-17 | 1972-12-26 | Special Metals Corp | Nickel base alloy |
| US3976482A (en) * | 1975-01-31 | 1976-08-24 | The International Nickel Company, Inc. | Method of making prealloyed thermoplastic powder and consolidated article |
| CA1109297A (en) * | 1976-10-12 | 1981-09-22 | David S. Duvall | Age hardenable nickel superalloy welding wires containing manganese |
| US4219592A (en) * | 1977-07-11 | 1980-08-26 | United Technologies Corporation | Two-way surfacing process by fusion welding |
| GB2148323B (en) * | 1983-07-29 | 1987-04-23 | Gen Electric | Nickel-base superalloy systems |
| JPS60116740A (en) * | 1983-11-30 | 1985-06-24 | Daido Steel Co Ltd | forging anvil |
-
1986
- 1986-11-14 DE DE19863638855 patent/DE3638855A1/en not_active Ceased
- 1986-11-17 GB GB08627438A patent/GB2183675A/en active Granted
- 1986-11-20 AU AU65580/86A patent/AU591198B2/en not_active Ceased
- 1986-11-20 CH CH4651/86A patent/CH677497A5/de not_active IP Right Cessation
- 1986-11-24 IL IL80732A patent/IL80732A/en not_active IP Right Cessation
- 1986-11-25 KR KR1019860009937A patent/KR930004478B1/en not_active Expired - Lifetime
- 1986-11-26 CN CN198686107041A patent/CN86107041A/en active Pending
- 1986-11-26 CA CA000523849A patent/CA1284592C/en not_active Expired - Lifetime
- 1986-11-26 FR FR8616481A patent/FR2592062B1/en not_active Expired
- 1986-11-26 JP JP61281619A patent/JPS62167835A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2592062A1 (en) | 1987-06-26 |
| CN86107041A (en) | 1987-07-15 |
| KR870005112A (en) | 1987-06-04 |
| IL80732A0 (en) | 1987-02-27 |
| GB8627438D0 (en) | 1986-12-17 |
| AU591198B2 (en) | 1989-11-30 |
| FR2592062B1 (en) | 1988-10-28 |
| KR930004478B1 (en) | 1993-05-27 |
| IL80732A (en) | 1989-08-15 |
| AU6558086A (en) | 1987-05-28 |
| JPH0430447B2 (en) | 1992-05-21 |
| JPS62167835A (en) | 1987-07-24 |
| DE3638855A1 (en) | 1987-05-27 |
| CH677497A5 (en) | 1991-05-31 |
| GB2183675A (en) | 1987-06-10 |
| GB2183675B (en) | 1989-10-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4810467A (en) | Nickel-base alloy | |
| US20040187973A1 (en) | Nickel base heat resistant cast alloy and turbine wheels made thereof | |
| US5882586A (en) | Heat-resistant nickel-based alloy excellent in weldability | |
| US4160066A (en) | Age-hardenable weld deposit | |
| US6139660A (en) | High corrosion resisting alloy for diesel engine valve and method for producing the valve | |
| US3401036A (en) | Valve steel | |
| CA1284592C (en) | Weldable cast nickel base superalloy | |
| US4871512A (en) | Alloys for exhaust valve | |
| SE8403851D0 (en) | NICKEL-BASE SUPERALLOY SYSTEMS | |
| US4095976A (en) | Weldable alloy | |
| US5223214A (en) | Heat treating furnace alloys | |
| CA1073249A (en) | Highly castable, weldable, corrosion resistant stainless steel | |
| US4750954A (en) | High temperature nickel base alloy with improved stability | |
| US4195987A (en) | Weldable alloys | |
| JPS63157795A (en) | Wire for high tensile steel | |
| US2891859A (en) | Alloy steel | |
| JPS5945752B2 (en) | Strong precipitation hardening austenitic heat resistant steel | |
| JPS6028900B2 (en) | Ni-based alloy for diesel engine valves and valve seats | |
| US5330705A (en) | Heat resistant alloys | |
| JPS5927369B2 (en) | Co-based alloy for diesel engine valves and valve seats | |
| US3925063A (en) | Electromagnetic stainless steel having excellent machinability | |
| US5516485A (en) | Weldable cast heat resistant alloy | |
| US4927602A (en) | Heat and corrosion resistant alloys | |
| JP3539120B2 (en) | Austenitic stainless steel with excellent hot workability | |
| CA1109298A (en) | Weldable alloy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |