CA1109297A - Age hardenable nickel superalloy welding wires containing manganese - Google Patents
Age hardenable nickel superalloy welding wires containing manganeseInfo
- Publication number
- CA1109297A CA1109297A CA285,086A CA285086A CA1109297A CA 1109297 A CA1109297 A CA 1109297A CA 285086 A CA285086 A CA 285086A CA 1109297 A CA1109297 A CA 1109297A
- Authority
- CA
- Canada
- Prior art keywords
- alloys
- weld
- cracking
- filler
- alloy
- 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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550 degrees C
- B23K35/3033—Ni as the principal constituent
- B23K35/304—Ni as the principal constituent with Cr as the next major constituent
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Arc Welding In General (AREA)
- Nonmetallic Welding Materials (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A class of age hardenable nickel base alloys for use as filler wires in fusion welding superalloys is described.
The alloys contain manganese in levels of from about .5 to 3 percent to greatly reduce the incidence of heat-affected zone cracking in the metal being welded. The weld filler alloys also contain significant amounts of aluminum, titanium, tantalum, and columbium, and therefore the resultant welds can be age hardened to relatively high strength levels.
Method for reducing cracking during fusion welding using above alloys are also disclosed.
A class of age hardenable nickel base alloys for use as filler wires in fusion welding superalloys is described.
The alloys contain manganese in levels of from about .5 to 3 percent to greatly reduce the incidence of heat-affected zone cracking in the metal being welded. The weld filler alloys also contain significant amounts of aluminum, titanium, tantalum, and columbium, and therefore the resultant welds can be age hardened to relatively high strength levels.
Method for reducing cracking during fusion welding using above alloys are also disclosed.
Description
~92~
DESCRIPTION OF THE PRIOR ART
Nickel base superalloys are widely used în high technology applications such as gas turbine engines. For certain applications it is necessary to join the nickel base superalloy ar~icles together by various welding processes. Great difficulties have been encountered in fusion welding superalloys and these difficulties largely involve crac~ing during or after the welding process.
Cracking commonly occurs both in the fused weld zone and in the parent material adjacent to the weld, i.e., the heat-affected zone. Prior art solutions to the superalloy cracking problem have largely involved the use of crack-resistant filler wire alloys which have relatively low strengths. ~ddition of these materials to the molten weld pool can successfully reduce the amount of crac~ing in the fused weld metal. ~Iowe~er, cracking is not necessarily prevented in the adjacent parent-metal heat~affected zone.
This approach also has an obvious drawback in that the weld zone will always be of lower strength than the super-alloy base metals being joined. The low strength nickel-base filler alloys used in t~e prior art ~ave not generally been of the type which is age hardenable; that is to say the prior art filler wire alloys have generally been low in aluminum, tita~ium, tantalum and columbium content.
Typical of these prior art alloys is that described in U.S. Patent 3,113,021. This alloy contains by weight about 20 percent chromium, about 1 percent iron, ~bout
DESCRIPTION OF THE PRIOR ART
Nickel base superalloys are widely used în high technology applications such as gas turbine engines. For certain applications it is necessary to join the nickel base superalloy ar~icles together by various welding processes. Great difficulties have been encountered in fusion welding superalloys and these difficulties largely involve crac~ing during or after the welding process.
Cracking commonly occurs both in the fused weld zone and in the parent material adjacent to the weld, i.e., the heat-affected zone. Prior art solutions to the superalloy cracking problem have largely involved the use of crack-resistant filler wire alloys which have relatively low strengths. ~ddition of these materials to the molten weld pool can successfully reduce the amount of crac~ing in the fused weld metal. ~Iowe~er, cracking is not necessarily prevented in the adjacent parent-metal heat~affected zone.
This approach also has an obvious drawback in that the weld zone will always be of lower strength than the super-alloy base metals being joined. The low strength nickel-base filler alloys used in t~e prior art ~ave not generally been of the type which is age hardenable; that is to say the prior art filler wire alloys have generally been low in aluminum, tita~ium, tantalum and columbium content.
Typical of these prior art alloys is that described in U.S. Patent 3,113,021. This alloy contains by weight about 20 percent chromium, about 1 percent iron, ~bout
2.5 percent columbium, about 3 percent manganese, about .2 percent silicon, about .35 percent titanium, and about Z.~,7 0.03 percent carbon, balance essentially nickel. The combined levels of aluminum, titanium, tantalum and columbium are less than 3 weight percent and this alloy would not exhibit any significant amount of age hardening response. Similar nickel base welding wire compositions are described in the Metals Handbook, Volume 6, page 284, however, once again these alloys are not age hardenable to any significant degree. Manganese is not a co~nmon alloying addition to age hardenable nickel base superalloys although in certain alloys it may be present in low levels, usually as an impurity.
SUMMARY OF THE I~VENTION
This invention involves a class of age hardenable nickel base weld wire compositions which reduce base metal cracking when fusion welding high strength nickel base superalloys. These weld filler alloys have uniquely tailored properties such that, when added during fusion welding, they favorably alter the stressJstrain dynamics responsible for cracking the parent-metal heat-affected zone during welding or post-weld heat treatment. A
principal benefit is derived from the addition of manganese to the filler alloys to reduce their melting point (solidus temperature). Other alloying elements which lower the solidus or alter properties do not produce the uni~ue benefits of the manganese additions. Weldments made with the filler wires of this invention can be age hardened to high strength levels because of the presence of the elements tantalum, columbium, aluminum, and titanium in the filler materials which precipitate the ~' and y " intermetallic com-pounds. The two basic types of alloys in this invention are those age hardened by the y' and yl' phases and those by the yt phase alone. For the y' and y" strengthened filler metals, ~the broad range of alloy compositions of the invention is, by weight, Ni, 14-22% Cr, 7-18% Fe, 0~5% CO~ 0-8% Mo, 0.5-1.5~o Al~
0-2.0% Ti, 2 ~ 5% Cb, 0-8% Ta, and 0. 5~ 3 . 0% Mn where the sum of Al + Ti + Cb + Ta is at least 5%. For the y' hardened mater-ials of the invention, the broad composition range is, by weight, Ni, 14-22% Cr, 5-15% CO~ 0~5% Fe, 0-8% Mo, 0.7~3% Al~ 0~5~4% Ti, 0-6% Cb + Ta, and 1. 5~3 . 0% Mn with the sum of Al + Ti at least
SUMMARY OF THE I~VENTION
This invention involves a class of age hardenable nickel base weld wire compositions which reduce base metal cracking when fusion welding high strength nickel base superalloys. These weld filler alloys have uniquely tailored properties such that, when added during fusion welding, they favorably alter the stressJstrain dynamics responsible for cracking the parent-metal heat-affected zone during welding or post-weld heat treatment. A
principal benefit is derived from the addition of manganese to the filler alloys to reduce their melting point (solidus temperature). Other alloying elements which lower the solidus or alter properties do not produce the uni~ue benefits of the manganese additions. Weldments made with the filler wires of this invention can be age hardened to high strength levels because of the presence of the elements tantalum, columbium, aluminum, and titanium in the filler materials which precipitate the ~' and y " intermetallic com-pounds. The two basic types of alloys in this invention are those age hardened by the y' and yl' phases and those by the yt phase alone. For the y' and y" strengthened filler metals, ~the broad range of alloy compositions of the invention is, by weight, Ni, 14-22% Cr, 7-18% Fe, 0~5% CO~ 0-8% Mo, 0.5-1.5~o Al~
0-2.0% Ti, 2 ~ 5% Cb, 0-8% Ta, and 0. 5~ 3 . 0% Mn where the sum of Al + Ti + Cb + Ta is at least 5%. For the y' hardened mater-ials of the invention, the broad composition range is, by weight, Ni, 14-22% Cr, 5-15% CO~ 0~5% Fe, 0-8% Mo, 0.7~3% Al~ 0~5~4% Ti, 0-6% Cb + Ta, and 1. 5~3 . 0% Mn with the sum of Al + Ti at least
3%. The yt and y~' filler wires are preferred when maximum weld-ability is required, along with high strength at intermediate use temperatures. The y' hardened filler alloys provide improv-ed weldability with the greatest possible high-temperature strength.
In accordance with a broad aspect of the invention, there is provided a method of reducing cracking in the gaseous tungsten arc welding of nickel base superalloy articles using 20 age hardenable nickel base filler material which consists essentially of a material selected from the group consisting of: -a) 14-22% Cr, 5-15% CO~ 0-5% Fe, 0-8% Mo, 0.7~3% Al, 0~5~4% Ti~
0-6% Ta+Cb, 0. 5~3% Mn, 0-0.1% C, 0-0. 05% B, 0-0.1% Zr, with the sum of Al+Ti exceeding 3%~ balance essentially ~i, and b) 14-22% Cr1 0~5% CO~ 7 18% Fe, 0-8% Mo, 0.5-1~5% Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0. 5~3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% ~r, Al+Ti~Cb+Ta in excess of 5%, balance essentially Ni.
BRIEF DESCRIPTION OF THE DRAWING
Figure 1 shows a correlation between the solidus temperature of a series of commercial and experimental nickel-base weld filler alloys and the incidence of heat-affected zone cracking during welding of a nickel base superalloy~
?? ~ .~ 7 Figure 2 shows a similar relationship bet~een relative amounts of heat-affected zone hot cracking and weld wire solidus temperatures for the preferred filler alloys of this invention and some co?.~nonly employed commercial filler alloys.
-4a-2~7 Figure 3 shows a correlation between the weld strength and the resistance to post-weld heat treatment cracking of the prior art alloys and the alloys of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
-Cracking problems encountered in welding nickel base superalloys can occur either during the solidification which follows the welding process or cluring subsequent heat treatments. The first type of cracking is called hot cracking and the second is termed post weld heat treatment ~PWHT) cracking. Although low strength filler wires are frequently used to minimize the occurrence of both types of cracking in the solidified weld metal~ they have not been nearly as successful in alleviating the problem in the heat-affected zone of the parent metal. Research has indicated that the metallurgical events which create a crack sensitive heat-affected zone condition in superalloys are inevitable consequences of the thermal cycles during fusion welding. Hence the best approach to the heat-affected zone problem is to favorably alter the stress/
strain dynamics during welding and post weld heat treatment to reduce cracking rather than trying to prevent damaging microstructural ckanges.
The present invention is related to the discovery that the additio~s of small amounts of manganese to a certain class of weld wire achieve this and greatly reduce the tendency for both types of heat-affected zone cracking.
2~7 The weld wire of the present invention is age hardenable to high strength and this feature is in marked contrast to the prior art filler wire compositions used in situa-tions where cracking is a problem. Preferably, the alloys are age hardenable by the precipitation of the ordered ` body centered tetragonal phase, Ni3 (Cb, Ta) commonly referred to as garnma double prime. This strengthening phase is preferred since the precipitation of the phase occurs relatively slowly, thus permitting a degree of stress relief by plastic accomrnodation before the strength of the filler wire increases significantly. Additions of small amounts of manganese have also been observed to impart weldability improvements in filler alloys which are strengthened by the formation of the ordered face centered cubic phase Ni3 (A1, Ti) commonly referred to as gamma prime. This hardening phase is beneficial when high strength is required at temperatures greater than approximately 850C (1562F).
The alloys of the invention which are hardened by precipitation of the y' phase will contain 14-22% Cr, 5-15% Co, 0-5% Fe, 0-8% Mo, .7-3% A1, .5-4% Ti, with the sum of A1 + Ti being at least 3%, 0-6% Ta + Cb, .5-3% Mn, up to .1% C, up to .05% B and up to .10% Zr. Preferably the Mn level will exceed 1.5%, the sum of Al + Ti will e~ceed 4%, the C level will fall in the range of .01-.04%, the B level will be less than .05% and the 2r level will be less than .08%. The balance of the alloy will be essentially nickél.
, -2~7 :
Those alloys of the invention which are hardened by precipitation of the y", with or without the ~' phase, will contain 14-22% Cr, 0-5jO Co, 7-18% Fe, 0-8% Mo, .5-1.5% Al, 0-2% Ti, 2~5% Cb, 0-8% Ta, with the sum of Al + Ti + Cb + Ta exceeding at least about 5%, .5-3% Mn, 0-~1% C, 0-.05%B, 0~ .10% Zr, balance essentially Ni. Preferably the y"
strengthened alloy contains .5-2.0% Mn, .01-.0~% C, .01-.02%
B and .01-.03% Zr.
~he addition of manganese is observed to reduce the incidence of both types of superalloy heat-affected zone cracking, despite the fact that manganese is deposited in the weld metal and apparently does not physically or chemically interact with the crack-sensitive heat-affected zone. A theory has been developed to explain the beneficial effect of manganese on heat-affected zone hot cracking.
This theory involves the effect of manganese on the solldus temperature of nickel base superalloys. Manganese generally has a fairly strong effect on the solidus temperature and the addition of 1 percent manganese to a nickel base super-alloy will typically depress the solidus temperature by atleast 50C (~ 93F). This reduction in solidus temperature means that a mangane~se-containing weld zone would solidify at a lower temperature and postpone the build-up of con-traction strains until the heat-affected æone had increased its strength and ductility upon cooliny. Figure 1 shows a correlation between the solidus temperature of various weld filler wires and the number of hot cracks observed in the heat-affected zone of the cast superalloy Inco* 713c after welding laboratory test specimens under fixed conditions.
* Trademark 2~7 ; The tests were designed to be severe enough-to cause at least some cracking with all filler wires so that a meaning-ful comparison could be made. The dotted line shows that the addition of relatively large amounts of manganese to pure nickel greatly reduces the incidence of cracking. The solid line shows a series of alloys which are used commercially for weld wire along with certain commercial alloys to which in-tentional additions of manganese have been made. The ~om-position of the commercial alloys is given in Table l. A
strong correlation can be seen between the solidus temperature ; and the propensity to crack during welding. Initially it ` was thought that the solidus temperature alone might influence the cracking tendency and a series of alloys based on Inconel~
718 were produced in whic~ other alloying elements (silicon, boron, and magnesium) known to reduce the solidus temperature were added. It can be seen J however, from Figure 1 that despite the reduction of the solidus temperature these alloying elements had a negligi~le e~fect on cracking tendency. Hence it appears that the beneficial properties associated with the depression of the solidus temperature ~re unique to manganese containing compositions.
Based upon these findings, an extensive evaluation was conducted of the welding characteristics and properties of weld wires of the present i.nvent~on (listed in Table II~
along with co~nercially used alloy compositions.
Hot cracking tests were conducted using tapered, cast-to-shape specimens of Inc~ 713c alloy. The specimens were 3.2 mm (0.125 in.) thick along the location of the test weld. Their tapered width produced a varying amount of 7 ~e~
z~
~ t.~
o l o ~d E~ d + `' +
"1 U ~ c~
U t~l I
_~
td E~ ¦ H ro o I o ~3 ¢~ t~ J
~1 , , C~i In '~ ~ u~ u~
~ ~tn ~ c~
; ~ 'H2 C ~ ¦ tV-U
, H
~ ~ ~,1 ¦ td ~d rd td td E~ U
O u~
p~
u~ O
Z ~1 E~ ~ r4 .
a + ~1 o ~
U~
3 t~
tr~ ~ ~ ~ o ~ ~
~1 ~ *o c~
P~
' ~;
u~ c~
:~ I c~1 o ~-~ Ci C~l C~
U~
C~
~d r.~
I '~
t~ E-llc~l I ~1 I t~ C~
¢ ~ ~ o o a~ u~c~
t) ~ r h a~¦ c~J c~
~i ~ Ln ~n ~ ~ u O b~ O
~ E~ O ~ ~ c~ ~ c~
¢æ ~3 ~æ ol c~
~ H C~l I
C~ E~
zH æ ~ c~", . .
E~ ~:4 H ræ~l L~
H ~: X
H E~ rlt~
~ rP~ z ~ ~P~
F~ O
~1 E-l ~ V~
r~
~:4 P: . .
O ~ ~ J
Z; ~ ~rl. ~P~ P' or~ r~_ E~
O ~ _ _ _ _ _ _ O ~1 c~
¢
: ', `.
~ 7 restraint (and propensity for cracking) from one end to the other of the welda~ility test specimen to insure that at least some cracking would be encountered in every test.
Following degreasing, the specimens were assem~led in a holding :Eixture for welding, and a controlled amount of the weld filler alloy in question was placed în a machined "v"
groove along the location for the test weld. The amount of weld filler wire added was closely measured such that each subsequent weld ended up as a homogeneous mixture of 30-40 volume percent filler alloy with the balance from the melted parent metal. The welds were made automatically ~y the gas-tungsten arc process in an evacuable welding chamber filled w;th high purity argon. ~11 welds were carried out at identical parameters: 75 amps welding current; 15 volts welding voltage; and 88.8 mm/min. (3.6 in.lmin) travel speed.
Following welding, the number and location of heat-affected - zone hot cracks were determined by optical examination at 25X magnification.
The results ~rom these tests confirmed the relationship between the filler wire solidus temperature and the degree of parent metal heat affected zone hot cracking. Figure 2 shows that welds made with the y' + y" strengthened filler wires of the present invention (Alloy Nos. 1, 2, 3 and 4) exhibited the least amount of heat-affected zone cracking.
Alloys 5 and 6 (~' strengthened fîller wires of this înven-tion) and two of the frequently utilized commercial filler wires produced welds with intermediate quantities of crac~ing, while other commercial filler wires gave poorer results.
~ ll ~
Weldability tests were also conducted using Waspaloy* parent metal to examine the effect of the filler wires of this invention on parent metal cracking during post-weld heat treatments. Waspaloy* is a commercial alloy which is difficult to weld. The test specimens consisted of 1.3-1.4 mm (0.051-0.055 in.) thick Waspaloy* sheet attached to 33 mm (1.3 in.) thick austenitic steel strong-backs to provide high degrees of restraint and residual welding stresses during post-weld heat treatment. The octagonal shaped Waspaloy* test specimens, 114.5 mm (4.5 in.) across faces, were first attached to the 133.4 mm (5.25 in.) diameter circular strongbacks by welding along the octagonal perimeter. A circular "U"-shaped groove, 50.8 mm (2.0 in.) in diameter, was machined around the center of specimen to provide a location for the test weld. The groove dimensions gave a subsequent weld consisting of 45-55 volume percent filler wire with the balance from the parent metal. The test welds were made by the manual gas-tungsten arc process using a rotating table, argon shielding, and the following parameters: welding current, 30 amps' weld travel speed, 88.8 mm/min. (3.6 in. min.). Following welding and inspect-ion, the test specimens attached to strongbacks were heated at an average rate of 9.SC/min. (17F~min.) to 843C (1550F) and held for four hours in a furnace atmosphere of argon.
Upon cooling in still air to room temperature, the test welds were inspected visually for evidence of cracking during the post-weld heat treatment.
Analysis of post-weld heat treatment tests showed that Alloys 3 and 4 of the present invention best reduced parent * Trademark '~7 metal cracking. Alloys 1, 2, and 6 had an intermediate effect, while Alloy 5 was less satisfactory. In comparison, the commercial filler wire Hastelloy* W also gave good results, the Inconel* 625 and Inconel* 718 filler wires were in the intermediate category, and Waspaloy* was least satisfactory.
Relative weld strengths were ascertained by testing castings composed of 50 weight percent filler alloy and 50 percent Waspaloy* to represent diluted welds. Yield strengths were measured at 843C (1550F) by compressive loading.
Results for some of the representative filler alloys are listed in Table III. It can be seen that the precipitation strengthened filler wires of the present invention provide considerably greater weld strength than is attainable with the non-age hardenable commercial filler wires.
The relative ranking of the alloys of the present invention compared to certain comrnercially used filler wires is listed in Table IV with respect to effects on both post-weld heat treatment cracking and hot cracking. Table IV
also compares the relative strength of the various filler alloys at both intermediate (e.g., 550-850C or 1022-1562F) and high temperatures e.g., greater than 850C (1562F).
It can be seen that the y' + y" strengthened experi-mental filler wires (Alloys 1-4) provide the best improvement to the heat-af~ected zone hot cracking problem and are as effective as any of the commercial alloys in alleviating post-weld heat treatment cracking.
Although the Hastelloy* W filler wire also effective-ly reduced post-weld heat treatment cracking, weld strength was low because of this alloy's non-age hardenable character.
* Trademark 2~7 TABLE III
EFFECT OF FILLER WIRE ON
ELEVATED-TEMPERATURE STRENGTH
Test Temperature: 843C (1550F) Test Material : Cast alloy of 50% ~iller alloy and 50% Waspaloy ~
0.2%
FILLER ALLOY YIELD STRENGT~I
; 2 Alloy No. 2 549.6 N/mm (79.7 ksi) Alloy No. 3 464.7 (67.4) Alloy No. 4 443.3 (64.3) Inconel~625 319.9 (46.4) Hastelloy~W 204.1 (29.6) Inconel'718 393.0 (57.0) Waspaloy SQ8.9 (73.8) ~ ,~
. .
: : ~
.
: ' ~r~
3;~7 TABLE IV
RELATIVE RANKING OF EFFECTS OF EXPERIMENTAL
AND COMMERCIAL WELD FILLER WIRES
ON I~LDMENT CRACKING AND STRENGTH
Relative Ranking of Benefit*
Cracking StrPngth Type of Inter. High Alloy Name Strengthening Hot Postweld Temp. Temp.
Alloy No. 1 y' + y" ppt. 1 2 1 2 Alloy No. 2 y' ~ y" ppt. 1 2 1 2 Alloy No. 3 y' + y" ppt. 1 1 1 2 Alloy No. 4 y ' + y" ppt . 2 1 1 2 Alloy No. 5 y' ppt. 2 3 Alloy No. 6 y' ppt . 2 2 2 Inconel 625 Non-ageable 2 2 3 3 Hastelloy W Non-ageable 3 l 3 3 Inconel~718 y' + y" ppt. 2 2 1 2 Waspaloy~ y' ppt 3 3 1 1 -* Relative Scale:
1 = Best 2 = Intermediate 3 = Poorest J~
3~ ~ 7 High strength welds could be achieved by use of Waspaloy filler wire, but the propensity for post-weld heat treatment cracking would be great. This relationship between weld strength and heat treatment cracking tendency is depicted in Figure 3 -- a plot o:E approximate weld s-trength and semi-quantitative cracking results for several weld wires. Figure 3 shows that the filler alloys of the present invention exceed the current weld strength/cracking resistance limitation as defined by the four baseline commercial filler wire alloys For instance, Alloy 3 gave cracking resistance equivalent to the best commercial filler wire, Hastelloy~W, combined with an estimated weld strength over twice that of Hastelloy W
(Table II~). Alloy 2 was equivalent to Inconel~718 filler wire in effect on post-weld heat treatment cracking but was approximately 40 percent stronger. In fact, it produced the strongest weld material tested at 843C ~1550F). The yl strengthened filler wires of the present invention do not significantly increase resistance to post-weld h at treat-ment cracking. However, they provide a means for achieving welds with good strengths at high temperature while reducing the amount of hot cracking commonly encountered when attempting to use current heat resistant, ~' strengthened filler wires such as Waspaloy (Table IV~. Thus, both the ~' and ~' + ~"
strengthened filler wires of thîs invention allow greater utility in the application of fusion welding for fabrication and repair of superalloys with poor weldability than is ; possible with existing methods.
Although the invention has been shown and described with respect to a preferred embodiment thereof, it should %b~
be understood by those skilled in the art that various changes and omissions in the form and detail thereof may be made therein and thereto without departing from the spirit and the scope of the invention.
:
.
In accordance with a broad aspect of the invention, there is provided a method of reducing cracking in the gaseous tungsten arc welding of nickel base superalloy articles using 20 age hardenable nickel base filler material which consists essentially of a material selected from the group consisting of: -a) 14-22% Cr, 5-15% CO~ 0-5% Fe, 0-8% Mo, 0.7~3% Al, 0~5~4% Ti~
0-6% Ta+Cb, 0. 5~3% Mn, 0-0.1% C, 0-0. 05% B, 0-0.1% Zr, with the sum of Al+Ti exceeding 3%~ balance essentially ~i, and b) 14-22% Cr1 0~5% CO~ 7 18% Fe, 0-8% Mo, 0.5-1~5% Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0. 5~3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% ~r, Al+Ti~Cb+Ta in excess of 5%, balance essentially Ni.
BRIEF DESCRIPTION OF THE DRAWING
Figure 1 shows a correlation between the solidus temperature of a series of commercial and experimental nickel-base weld filler alloys and the incidence of heat-affected zone cracking during welding of a nickel base superalloy~
?? ~ .~ 7 Figure 2 shows a similar relationship bet~een relative amounts of heat-affected zone hot cracking and weld wire solidus temperatures for the preferred filler alloys of this invention and some co?.~nonly employed commercial filler alloys.
-4a-2~7 Figure 3 shows a correlation between the weld strength and the resistance to post-weld heat treatment cracking of the prior art alloys and the alloys of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
-Cracking problems encountered in welding nickel base superalloys can occur either during the solidification which follows the welding process or cluring subsequent heat treatments. The first type of cracking is called hot cracking and the second is termed post weld heat treatment ~PWHT) cracking. Although low strength filler wires are frequently used to minimize the occurrence of both types of cracking in the solidified weld metal~ they have not been nearly as successful in alleviating the problem in the heat-affected zone of the parent metal. Research has indicated that the metallurgical events which create a crack sensitive heat-affected zone condition in superalloys are inevitable consequences of the thermal cycles during fusion welding. Hence the best approach to the heat-affected zone problem is to favorably alter the stress/
strain dynamics during welding and post weld heat treatment to reduce cracking rather than trying to prevent damaging microstructural ckanges.
The present invention is related to the discovery that the additio~s of small amounts of manganese to a certain class of weld wire achieve this and greatly reduce the tendency for both types of heat-affected zone cracking.
2~7 The weld wire of the present invention is age hardenable to high strength and this feature is in marked contrast to the prior art filler wire compositions used in situa-tions where cracking is a problem. Preferably, the alloys are age hardenable by the precipitation of the ordered ` body centered tetragonal phase, Ni3 (Cb, Ta) commonly referred to as garnma double prime. This strengthening phase is preferred since the precipitation of the phase occurs relatively slowly, thus permitting a degree of stress relief by plastic accomrnodation before the strength of the filler wire increases significantly. Additions of small amounts of manganese have also been observed to impart weldability improvements in filler alloys which are strengthened by the formation of the ordered face centered cubic phase Ni3 (A1, Ti) commonly referred to as gamma prime. This hardening phase is beneficial when high strength is required at temperatures greater than approximately 850C (1562F).
The alloys of the invention which are hardened by precipitation of the y' phase will contain 14-22% Cr, 5-15% Co, 0-5% Fe, 0-8% Mo, .7-3% A1, .5-4% Ti, with the sum of A1 + Ti being at least 3%, 0-6% Ta + Cb, .5-3% Mn, up to .1% C, up to .05% B and up to .10% Zr. Preferably the Mn level will exceed 1.5%, the sum of Al + Ti will e~ceed 4%, the C level will fall in the range of .01-.04%, the B level will be less than .05% and the 2r level will be less than .08%. The balance of the alloy will be essentially nickél.
, -2~7 :
Those alloys of the invention which are hardened by precipitation of the y", with or without the ~' phase, will contain 14-22% Cr, 0-5jO Co, 7-18% Fe, 0-8% Mo, .5-1.5% Al, 0-2% Ti, 2~5% Cb, 0-8% Ta, with the sum of Al + Ti + Cb + Ta exceeding at least about 5%, .5-3% Mn, 0-~1% C, 0-.05%B, 0~ .10% Zr, balance essentially Ni. Preferably the y"
strengthened alloy contains .5-2.0% Mn, .01-.0~% C, .01-.02%
B and .01-.03% Zr.
~he addition of manganese is observed to reduce the incidence of both types of superalloy heat-affected zone cracking, despite the fact that manganese is deposited in the weld metal and apparently does not physically or chemically interact with the crack-sensitive heat-affected zone. A theory has been developed to explain the beneficial effect of manganese on heat-affected zone hot cracking.
This theory involves the effect of manganese on the solldus temperature of nickel base superalloys. Manganese generally has a fairly strong effect on the solidus temperature and the addition of 1 percent manganese to a nickel base super-alloy will typically depress the solidus temperature by atleast 50C (~ 93F). This reduction in solidus temperature means that a mangane~se-containing weld zone would solidify at a lower temperature and postpone the build-up of con-traction strains until the heat-affected æone had increased its strength and ductility upon cooliny. Figure 1 shows a correlation between the solidus temperature of various weld filler wires and the number of hot cracks observed in the heat-affected zone of the cast superalloy Inco* 713c after welding laboratory test specimens under fixed conditions.
* Trademark 2~7 ; The tests were designed to be severe enough-to cause at least some cracking with all filler wires so that a meaning-ful comparison could be made. The dotted line shows that the addition of relatively large amounts of manganese to pure nickel greatly reduces the incidence of cracking. The solid line shows a series of alloys which are used commercially for weld wire along with certain commercial alloys to which in-tentional additions of manganese have been made. The ~om-position of the commercial alloys is given in Table l. A
strong correlation can be seen between the solidus temperature ; and the propensity to crack during welding. Initially it ` was thought that the solidus temperature alone might influence the cracking tendency and a series of alloys based on Inconel~
718 were produced in whic~ other alloying elements (silicon, boron, and magnesium) known to reduce the solidus temperature were added. It can be seen J however, from Figure 1 that despite the reduction of the solidus temperature these alloying elements had a negligi~le e~fect on cracking tendency. Hence it appears that the beneficial properties associated with the depression of the solidus temperature ~re unique to manganese containing compositions.
Based upon these findings, an extensive evaluation was conducted of the welding characteristics and properties of weld wires of the present i.nvent~on (listed in Table II~
along with co~nercially used alloy compositions.
Hot cracking tests were conducted using tapered, cast-to-shape specimens of Inc~ 713c alloy. The specimens were 3.2 mm (0.125 in.) thick along the location of the test weld. Their tapered width produced a varying amount of 7 ~e~
z~
~ t.~
o l o ~d E~ d + `' +
"1 U ~ c~
U t~l I
_~
td E~ ¦ H ro o I o ~3 ¢~ t~ J
~1 , , C~i In '~ ~ u~ u~
~ ~tn ~ c~
; ~ 'H2 C ~ ¦ tV-U
, H
~ ~ ~,1 ¦ td ~d rd td td E~ U
O u~
p~
u~ O
Z ~1 E~ ~ r4 .
a + ~1 o ~
U~
3 t~
tr~ ~ ~ ~ o ~ ~
~1 ~ *o c~
P~
' ~;
u~ c~
:~ I c~1 o ~-~ Ci C~l C~
U~
C~
~d r.~
I '~
t~ E-llc~l I ~1 I t~ C~
¢ ~ ~ o o a~ u~c~
t) ~ r h a~¦ c~J c~
~i ~ Ln ~n ~ ~ u O b~ O
~ E~ O ~ ~ c~ ~ c~
¢æ ~3 ~æ ol c~
~ H C~l I
C~ E~
zH æ ~ c~", . .
E~ ~:4 H ræ~l L~
H ~: X
H E~ rlt~
~ rP~ z ~ ~P~
F~ O
~1 E-l ~ V~
r~
~:4 P: . .
O ~ ~ J
Z; ~ ~rl. ~P~ P' or~ r~_ E~
O ~ _ _ _ _ _ _ O ~1 c~
¢
: ', `.
~ 7 restraint (and propensity for cracking) from one end to the other of the welda~ility test specimen to insure that at least some cracking would be encountered in every test.
Following degreasing, the specimens were assem~led in a holding :Eixture for welding, and a controlled amount of the weld filler alloy in question was placed în a machined "v"
groove along the location for the test weld. The amount of weld filler wire added was closely measured such that each subsequent weld ended up as a homogeneous mixture of 30-40 volume percent filler alloy with the balance from the melted parent metal. The welds were made automatically ~y the gas-tungsten arc process in an evacuable welding chamber filled w;th high purity argon. ~11 welds were carried out at identical parameters: 75 amps welding current; 15 volts welding voltage; and 88.8 mm/min. (3.6 in.lmin) travel speed.
Following welding, the number and location of heat-affected - zone hot cracks were determined by optical examination at 25X magnification.
The results ~rom these tests confirmed the relationship between the filler wire solidus temperature and the degree of parent metal heat affected zone hot cracking. Figure 2 shows that welds made with the y' + y" strengthened filler wires of the present invention (Alloy Nos. 1, 2, 3 and 4) exhibited the least amount of heat-affected zone cracking.
Alloys 5 and 6 (~' strengthened fîller wires of this înven-tion) and two of the frequently utilized commercial filler wires produced welds with intermediate quantities of crac~ing, while other commercial filler wires gave poorer results.
~ ll ~
Weldability tests were also conducted using Waspaloy* parent metal to examine the effect of the filler wires of this invention on parent metal cracking during post-weld heat treatments. Waspaloy* is a commercial alloy which is difficult to weld. The test specimens consisted of 1.3-1.4 mm (0.051-0.055 in.) thick Waspaloy* sheet attached to 33 mm (1.3 in.) thick austenitic steel strong-backs to provide high degrees of restraint and residual welding stresses during post-weld heat treatment. The octagonal shaped Waspaloy* test specimens, 114.5 mm (4.5 in.) across faces, were first attached to the 133.4 mm (5.25 in.) diameter circular strongbacks by welding along the octagonal perimeter. A circular "U"-shaped groove, 50.8 mm (2.0 in.) in diameter, was machined around the center of specimen to provide a location for the test weld. The groove dimensions gave a subsequent weld consisting of 45-55 volume percent filler wire with the balance from the parent metal. The test welds were made by the manual gas-tungsten arc process using a rotating table, argon shielding, and the following parameters: welding current, 30 amps' weld travel speed, 88.8 mm/min. (3.6 in. min.). Following welding and inspect-ion, the test specimens attached to strongbacks were heated at an average rate of 9.SC/min. (17F~min.) to 843C (1550F) and held for four hours in a furnace atmosphere of argon.
Upon cooling in still air to room temperature, the test welds were inspected visually for evidence of cracking during the post-weld heat treatment.
Analysis of post-weld heat treatment tests showed that Alloys 3 and 4 of the present invention best reduced parent * Trademark '~7 metal cracking. Alloys 1, 2, and 6 had an intermediate effect, while Alloy 5 was less satisfactory. In comparison, the commercial filler wire Hastelloy* W also gave good results, the Inconel* 625 and Inconel* 718 filler wires were in the intermediate category, and Waspaloy* was least satisfactory.
Relative weld strengths were ascertained by testing castings composed of 50 weight percent filler alloy and 50 percent Waspaloy* to represent diluted welds. Yield strengths were measured at 843C (1550F) by compressive loading.
Results for some of the representative filler alloys are listed in Table III. It can be seen that the precipitation strengthened filler wires of the present invention provide considerably greater weld strength than is attainable with the non-age hardenable commercial filler wires.
The relative ranking of the alloys of the present invention compared to certain comrnercially used filler wires is listed in Table IV with respect to effects on both post-weld heat treatment cracking and hot cracking. Table IV
also compares the relative strength of the various filler alloys at both intermediate (e.g., 550-850C or 1022-1562F) and high temperatures e.g., greater than 850C (1562F).
It can be seen that the y' + y" strengthened experi-mental filler wires (Alloys 1-4) provide the best improvement to the heat-af~ected zone hot cracking problem and are as effective as any of the commercial alloys in alleviating post-weld heat treatment cracking.
Although the Hastelloy* W filler wire also effective-ly reduced post-weld heat treatment cracking, weld strength was low because of this alloy's non-age hardenable character.
* Trademark 2~7 TABLE III
EFFECT OF FILLER WIRE ON
ELEVATED-TEMPERATURE STRENGTH
Test Temperature: 843C (1550F) Test Material : Cast alloy of 50% ~iller alloy and 50% Waspaloy ~
0.2%
FILLER ALLOY YIELD STRENGT~I
; 2 Alloy No. 2 549.6 N/mm (79.7 ksi) Alloy No. 3 464.7 (67.4) Alloy No. 4 443.3 (64.3) Inconel~625 319.9 (46.4) Hastelloy~W 204.1 (29.6) Inconel'718 393.0 (57.0) Waspaloy SQ8.9 (73.8) ~ ,~
. .
: : ~
.
: ' ~r~
3;~7 TABLE IV
RELATIVE RANKING OF EFFECTS OF EXPERIMENTAL
AND COMMERCIAL WELD FILLER WIRES
ON I~LDMENT CRACKING AND STRENGTH
Relative Ranking of Benefit*
Cracking StrPngth Type of Inter. High Alloy Name Strengthening Hot Postweld Temp. Temp.
Alloy No. 1 y' + y" ppt. 1 2 1 2 Alloy No. 2 y' ~ y" ppt. 1 2 1 2 Alloy No. 3 y' + y" ppt. 1 1 1 2 Alloy No. 4 y ' + y" ppt . 2 1 1 2 Alloy No. 5 y' ppt. 2 3 Alloy No. 6 y' ppt . 2 2 2 Inconel 625 Non-ageable 2 2 3 3 Hastelloy W Non-ageable 3 l 3 3 Inconel~718 y' + y" ppt. 2 2 1 2 Waspaloy~ y' ppt 3 3 1 1 -* Relative Scale:
1 = Best 2 = Intermediate 3 = Poorest J~
3~ ~ 7 High strength welds could be achieved by use of Waspaloy filler wire, but the propensity for post-weld heat treatment cracking would be great. This relationship between weld strength and heat treatment cracking tendency is depicted in Figure 3 -- a plot o:E approximate weld s-trength and semi-quantitative cracking results for several weld wires. Figure 3 shows that the filler alloys of the present invention exceed the current weld strength/cracking resistance limitation as defined by the four baseline commercial filler wire alloys For instance, Alloy 3 gave cracking resistance equivalent to the best commercial filler wire, Hastelloy~W, combined with an estimated weld strength over twice that of Hastelloy W
(Table II~). Alloy 2 was equivalent to Inconel~718 filler wire in effect on post-weld heat treatment cracking but was approximately 40 percent stronger. In fact, it produced the strongest weld material tested at 843C ~1550F). The yl strengthened filler wires of the present invention do not significantly increase resistance to post-weld h at treat-ment cracking. However, they provide a means for achieving welds with good strengths at high temperature while reducing the amount of hot cracking commonly encountered when attempting to use current heat resistant, ~' strengthened filler wires such as Waspaloy (Table IV~. Thus, both the ~' and ~' + ~"
strengthened filler wires of thîs invention allow greater utility in the application of fusion welding for fabrication and repair of superalloys with poor weldability than is ; possible with existing methods.
Although the invention has been shown and described with respect to a preferred embodiment thereof, it should %b~
be understood by those skilled in the art that various changes and omissions in the form and detail thereof may be made therein and thereto without departing from the spirit and the scope of the invention.
:
.
Claims (5)
1. A method of reducing cracking in the gaseous tungsten arc welding of nickel base superalloy articles using age hardenable nickel base filler material which consists essentially of a material selected from the group consisting of:
a) 14-22% Cr, 5-15% Co, 0-5% Fe, 0-8% Mo, 0.7-3% Al, 0.5-4% Ti, 0-6% Ta+Cb, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.1% Zr, with the sum of Al+Ti exceeding 3%, balance essentially Ni; and b) 14-22% Cr, 0-5% Co, 7-18% Fe, 0-8% Mo, 0.5-1.5% Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% Zr, Al+Ti+Cb+Ta in excess of 5%, balance essentially Ni.
a) 14-22% Cr, 5-15% Co, 0-5% Fe, 0-8% Mo, 0.7-3% Al, 0.5-4% Ti, 0-6% Ta+Cb, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.1% Zr, with the sum of Al+Ti exceeding 3%, balance essentially Ni; and b) 14-22% Cr, 0-5% Co, 7-18% Fe, 0-8% Mo, 0.5-1.5% Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% Zr, Al+Ti+Cb+Ta in excess of 5%, balance essentially Ni.
2. A method for reducing cracking in the gaseous tungsten arc welding of nickel base superalloy articles using age hardenable nickel base filler material which consists essentially of 14-22% Cr, 5-15% Co, 0-5% Fe, 0-8% Mo, 0.7-3%
Al, 0.5-4% Ti, 0-6% Ta+Cb, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.1%
Zr, with the sum of Al+Ti exceeding 3%, balance essentially Ni.
Al, 0.5-4% Ti, 0-6% Ta+Cb, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.1%
Zr, with the sum of Al+Ti exceeding 3%, balance essentially Ni.
3. A method for reducing cracking in the gaseous tungsten arc welding of nickel base superalloy articles using age hardenable nickel base filler material which consists essentially of 14-22% Cr, 0-5% Co, 7-18% Fe, 0-8% Mo, 0.5-1.5%
Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% Zr, Al+Ti+Cb+Ta in excess of 5%, balance essentially Ni.
Al, 0-2% Ti, 2-5% Cb, 0-8% Ta, 0.5-3% Mn, 0-0.1% C, 0-0.05% B, 0-0.08% Zr, Al+Ti+Cb+Ta in excess of 5%, balance essentially Ni.
4. A method as in claim 2 wherein the sum of Al + Ti exceeds 4% and the Mn level exceeds about 1.5%.
5. A method according to claim 3 wherein Mn level is about 0.5-2.0%.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US73141076A | 1976-10-12 | 1976-10-12 | |
| US731,410 | 1976-10-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1109297A true CA1109297A (en) | 1981-09-22 |
Family
ID=24939378
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA285,086A Expired CA1109297A (en) | 1976-10-12 | 1977-08-19 | Age hardenable nickel superalloy welding wires containing manganese |
Country Status (12)
| Country | Link |
|---|---|
| JP (1) | JPS5347322A (en) |
| AU (1) | AU513550B2 (en) |
| BE (1) | BE858931A (en) |
| BR (1) | BR7706447A (en) |
| CA (1) | CA1109297A (en) |
| DE (1) | DE2744085A1 (en) |
| FR (1) | FR2367573A1 (en) |
| GB (1) | GB1592407A (en) |
| IL (1) | IL52971A (en) |
| IT (1) | IT1085191B (en) |
| NO (1) | NO147262C (en) |
| SE (1) | SE7710617L (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4219592A (en) * | 1977-07-11 | 1980-08-26 | United Technologies Corporation | Two-way surfacing process by fusion welding |
| US4507264A (en) * | 1982-12-01 | 1985-03-26 | Alloy Metals, Inc. | Nickel base brazing alloy and method |
| JPS60211028A (en) * | 1984-04-03 | 1985-10-23 | Daido Steel Co Ltd | Alloy for exhaust valve |
| DE3638855A1 (en) * | 1985-11-26 | 1987-05-27 | United Technologies Corp | NICKEL-BASED SUPER ALLOY |
| US4810467A (en) * | 1987-08-06 | 1989-03-07 | General Electric Company | Nickel-base alloy |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB880805A (en) * | 1958-11-26 | 1961-10-25 | Rolls Royce | Nickel-chromium-cobalt alloys |
| FR1368921A (en) * | 1962-11-21 | 1964-08-07 | Int Nickel Co | coated welding electrode |
| GB1070099A (en) * | 1965-06-25 | 1967-05-24 | Int Nickel Ltd | Welding high-temperature alloys |
| DE2242236A1 (en) * | 1972-08-28 | 1974-03-07 | Ver Deutsche Metallwerke Ag | WELDING MATERIAL |
-
1977
- 1977-08-19 CA CA285,086A patent/CA1109297A/en not_active Expired
- 1977-09-20 IL IL52971A patent/IL52971A/en unknown
- 1977-09-20 FR FR7728284A patent/FR2367573A1/en active Pending
- 1977-09-21 IT IT27805/77A patent/IT1085191B/en active
- 1977-09-21 GB GB39336/77A patent/GB1592407A/en not_active Expired
- 1977-09-21 JP JP11388577A patent/JPS5347322A/en active Pending
- 1977-09-22 BE BE181098A patent/BE858931A/en unknown
- 1977-09-22 SE SE7710617A patent/SE7710617L/en not_active Application Discontinuation
- 1977-09-22 AU AU29011/77A patent/AU513550B2/en not_active Expired
- 1977-09-26 NO NO773281A patent/NO147262C/en unknown
- 1977-09-28 BR BR7706447A patent/BR7706447A/en unknown
- 1977-09-30 DE DE19772744085 patent/DE2744085A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| FR2367573A1 (en) | 1978-05-12 |
| IL52971A (en) | 1981-02-27 |
| AU513550B2 (en) | 1980-12-11 |
| GB1592407A (en) | 1981-07-08 |
| JPS5347322A (en) | 1978-04-27 |
| DE2744085A1 (en) | 1978-04-13 |
| IL52971A0 (en) | 1977-11-30 |
| NO147262C (en) | 1983-03-09 |
| BR7706447A (en) | 1978-06-27 |
| SE7710617L (en) | 1978-04-13 |
| IT1085191B (en) | 1985-05-28 |
| NO147262B (en) | 1982-11-29 |
| AU2901177A (en) | 1979-03-29 |
| BE858931A (en) | 1978-01-16 |
| NO773281L (en) | 1978-04-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4213026A (en) | Age hardenable nickel superalloy welding wires containing manganese | |
| Ramkumar et al. | Investigations on the microstructure, tensile strength and high temperature corrosion behaviour of Inconel 625 and Inconel 718 dissimilar joints | |
| US4415530A (en) | Nickel-base welding alloy | |
| CA2898313C (en) | Precipitation strengthened nickel based welding material for fusion welding of superalloys | |
| CA1333342C (en) | Nickel-base alloy | |
| EP2902516A1 (en) | A weld filler for nickel-base superalloys | |
| US4336312A (en) | Weldable nickel base cast alloy for high temperature applications and method | |
| EP1420074A2 (en) | Nickel-base alloy and its use in casting and welding operations | |
| EP1197570B1 (en) | Nickel-base alloy and its use in forging and welding operations | |
| CA1109297A (en) | Age hardenable nickel superalloy welding wires containing manganese | |
| EP0260600B1 (en) | High temperature nickel base alloy with improved stability | |
| Uygur et al. | The effect of TIG welding on microstructure and mechanical properties of a butt-joined-unalloyed titanium | |
| US6284392B1 (en) | Superalloys with improved weldability for high temperature applications | |
| US3970447A (en) | Ferritic steel welding material | |
| CA2850698C (en) | Welding material for welding of superalloys | |
| GB2048146A (en) | Process for treating weldments | |
| Maguire et al. | Weldability of alloy 718, 625 and variants | |
| Tzeng et al. | Effect of Inconel 625 on microstructure and mechanical properties of gas tungsten arc welded Inconel-713LC superalloy joints | |
| EP4357050A1 (en) | High gamma prime nickel based welding material for repair and 3d additive manufacturing of turbine engine components | |
| GB2075057A (en) | Nickel base superalloy | |
| Vishwakarma | Microstructural analysis of weld cracking in 718 Plus superalloy | |
| Borhani et al. | Investigating the solidification microstructure of IN625 superalloy cladded by direct laser deposition process on IN713LC | |
| Kayano et al. | Effect of Ni content on solidification cracking susceptibility of Inconel 706 Ni-base superalloy | |
| Buyukyildirim et al. | The effect of shielding gas on the toughness of AlMg4. 5Mn weld metals made by GMAW | |
| Manikandan et al. | Welding of Alloy C-276 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |