DE1812336A1 - Nickel alloy resistant to sulfiding attack - Google Patents

Description

■ ■ "■ ' "■ '■■' '"' ■ ■: - .. ■■ (■! Ii-'j; · '·' !! ¹ '■;■"' SjI ^l ■ ·! ■■ '·· ' ■■■■ ■■ · .-: · -! ■■. '!! \; ..' · "<'/: J ₁ ; 11).: Rw ■ -1. Τ,» ι. ■■■ ■.,,

Dr. Ing. E. BERKENFELD ■ Dipl.-I ng. H. B ERKEN FE LD, patent attorneys, Cologne

Attachment file number

on the submission of December 2, 1963 Sch Name d. Note UNITED AIRCRAFT CORPORATION

Gagen sulfidizing attack resistant nickel alloy.

The invention relates to non-ferrous alloys, which are particularly desirable Properties in terms of corrosion resistance with combine good values of mechanical properties. The invention relates in particular to nickel alloys, the selected alloy components in one desired Contain quantitative ratio and which are particularly suitable for use at high temperatures in corrosive and abrasive areas Atmosphere of gas turbine engines.

Nickel alloys have been and are heretofore used for numerous uses in which they are high temperature and are exposed to a corrosive and abrasive environment. Such alloys are particularly advantageous in use to turbine blades and blades of gas turbine engines, where they are at temperatures of 815 - 1090 ° C and above in a highly corrosive and erosive atmosphere. Examples for known alloys that have been used or are suitable for the production of turbine blades and / or turbine blades are described in U.S. Patent 3,310,299 and also represent commercially available alloys, such as

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the Udimet 700 cast alloy available from Special Metall, Inc. However, the known alloys do not have the desired level of resistance to sulfidizing erosion and oxidizing erosion, especially if the alloy is used in addition, the combination of good mechanical components required for the manufacture of turbine blades and / or turbine blades Possesses properties. The terms "sulphidating erosion" and "oxidative erosion" have come to be known in the literature the sulfidation and oxidation used and are used in the description of the invention in the same sense will. Sulphidizing erosion is a special problem in aircraft gas turbines, in which there are atmospheric elements combine with products of combustion and have a disastrous effect on the hot turune blades. Furthermore it was necessary for previously known alloys with improved properties with regard to sulphidating erosion, to forego the resistance to oxidizing erosion and the strength in order to achieve the desired properties to achieve in terms of sulfiding erosion.

The invention avoids the disadvantages of the known nickel alloys, especially the alloys used for turbine blades and blades in plug-in type gas turbine engines will. According to the invention there is a new and improved nickel alloy created, which has a combination of excellent mechanical properties and a significantly increased resistance against sulfidizing erosion and oxidizing erosion having.

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The subject of the invention is a nickel alloy resistant to sulfidizing attack, which is characterized by the content of joining alloy components: 10-20% by weight of chromium,

2 -13 wt -.% Aluminum,
1 - 3 wt. Y & titanium,
3 * 5-7.5 wt .- ^ tantalum,

3 - Ό wt .-> i> Tungsten,

1 - 3 wt .-; i molybdenum,

5-20 wt -.% Cobalt,

0 - 0, O5 weight jio boron,

0 - 0.1 wt .-> «zircon,

0 - 0.5 wt .- ^ carbon,

The remainder essentially nickel.

The upper limit of the molybdenum content is preferably 1.5 $ and the molybdenum content used up to this preferred maximum content is selected in such a way that the beneficial effect of the molybdenum present in the alloys together with chromium on sulfidation against the deteriorating effectiveness of molybdenum together with titanium is achieved or cobalt in the alloy. It was also found that a proportion of about Ky ₀ tantalum also makes a strong contribution to good resistance to sulfidizing attack, and also appears to bring about good properties with regard to oxidation resistance and at the same time meets the requirements of alloy stability.

It appears that tantalum is not interchangeable with niobium in the alloy according to the invention.

u 6/12 * 909825/11 98

The new and improved nickel alloys of the invention are resistant to corrosion and erosion, suIfidation erosion, Oxidation erosion and at the same time have good properties with regard to oxidation erosion.

The nickel alloys according to the invention are particularly good for Use in gas turbine engines and suitable for the manufacture of turbine blades and / or turbine blades for gas turbine engines.

The advantages achieved by the invention and other embodiments Forms of embodiment of the invention can be found in the following description and the drawings.

In these drawings, Figures 1-5 represent graphic representations, in which the weight loss is plotted against time for various of the experiments described.

Pig. 6 is a graph showing the effect of the effect of various elements on suIfidation properties.

Within the range of alloy constituents specified according to the invention, the following, narrower range is preferred because of the high degree of alloy stability desired: 15-17 % chromium, (% by weight )
3.7 to 4.5 $ aluminum, "
1.5-2.3 % titanium, "
3.25-4.5 % tantalum, "
4.0-5.5 % tungsten, "
$ 1.0 - $ 1.75 molybdenum, "

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9-11 wt $ cobalt, 0.01-0.02 wt $ boron, 0.05-0.10 wt. $ Zirconium, 0.10-0.15 wt. $ Carbon, The remainder essentially nickel.

A particularly favorable range of alloy composition in wt .- $:

$ 14-15 chrome, $ 3.7 - $ 4.3 aluminum, $ 1.7 - $ 2.0 titanium,

$ 3.5 - $ 4.25 tantalum,

$ 4.5 - $ 5.5 tungsten,

$ 1.25 - $ 1.5 molybdenum,

$ 9.5 - $ 10.5 cobalt,

$ 0.01-0.02 boron,

$ 0.05 - $ 0.10 zircon,

0.10 - 0.15 $ carbon,

The remainder essentially nickel.

The following laying composition is particularly preferred in wt .- $:

$ 15 chrome,
$ 4.0 aluminum, $ 2.0 titanium,
$ 4.0 tantalum, $ 5.0 tungsten,

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1.5 % molybdenum, L ^

10 % cobalt, ■ '■ ·

0.015 % boron,

0.075 % zircon,

0.105 % carbon,

The remainder essentially nickel.

The following are examples of manufacture and test results given for various formulations of the nickel alloy according to the invention that are within the stated ranges the composition lie.

The percentages given in the examples are percentages by weight.

example 1

An alloy melt (alloy T.) was produced according to the invention, which had the following composition in terms of weight:
Element alloy T ^

C 0.14 %

B 0.021 %

Zr 0.08 % '

Cr 14.75 % -. '

Al 3.89 %

Ti -. 1.68 %

Ta 4.16 %

Mon 1.56 %

co 9.78 % ;

W 4.79 % ■,

Ni rest. <

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78 7233 B

The alloy was produced in the following ways: * ■

1. Chromium, tantalum, molybdenum, cobalt, tungsten and nickel were made first put in the furnace.

2. The batch was melted and held at 1454 ° C for 15 minutes.

3. (a) Zr and NiB, (b) CrC, and (c) Al and Ti were used in this Order separately added in a proportion of $ 40, being was stirred for 3 minutes after each addition.

4. The melt was held at 1454 ° C for 10 minutes and then to test bars with a length of 7.62 cm and one Potted in a diameter of 1.27 cm.

In addition, comparison samples (alloy CS ..) were produced for comparison tests in the form of test bars of the same size. Alloy CS ₁ is described in U.S. Patent 3,310,399. The comparison samples had the following composition in wt .-? &:

Element alloy CS ₁

C 0.10 %

B 0.017 %

Zr 0.07 %

Cr 7.80 %

Al 5.99 %

Ti 1.03 %

Ta 4.37 %

Mon 5.90 %

Co 10.15 %

Nl 'rest

Then an isothermal sulfidation erosion test was carried out by reacting both the test bars as well as the control samples for 150 hours at 982 ⁰ C sulfiding conditions

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by placing them in the flow path of the combustion products of JP-5R nozzles and adding 3.5 parts per million parts of synthetic sea salt to the combustion products. The composition of the synthetic sea salt solution was as follows: 18.9 1 HgO, 3.76 g NaCl, 0.60 g Na ₂ SO ^, 0.19 g CaCl ₂ , 1.16 g M Cl ₂ .6H ₂ O.

The results obtained by this test of sulfidizing erosion with the alloy T ₁ according to Example 1 and the comparative _{samples CS 1} are shown in the following table:

Alloy weight loss up to the visible

Damage, elapsed time

0.41 113.0 hours

6.94 18.0 hours

Alloys according to US Pat. No. 3,310,399 are noted for high strength properties and good. Oxidation properties known, but they have poor sulfidation properties. As can be readily seen from the results in the table, alloy T ₁ showed significantly superior sulfidation resistance to the comparative _{samples of CS 1} , both in terms of weight loss and the occurrence of visible damage.

Example 2

An alloy according to the invention with the procedure given in Example 1 below T ₁ composition in wt .- / & was comparable to that described in Example 1 into test bars of the same size

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pour. In addition, comparative samples were prepared of the same size whose composition Ln "wt, -.. / Prepared ₀ corresponded -were addition, test bars of the same size made of cast alloy Udirnet 700 £ those used in Example 1 Comparative Samples CS having the following composition in percent by -p. had:

Element · alloy C3 _p

C 0.06

B 0.035

Zr 0.03

Cr 14.41

Al 4.43

Ti 3.41 Mo 4.80

Co '19, 27

Ni rest.

It is known that Udirnet 700 average in comparison with alloys according to US Patent 3,310,399 strength, poorer Oxidationsbe st resistance and has approximately the same resistance to sulfidation.

The test rods were used to carry out an oxidation-erosion test made of alloy T. and the comparison samples made of alloy CS., And C3p in the flow path of the products of combustion of JP-5R ~ nozzles placed and subjected to the following cycles:

1. 3 minutes exposure to products of combustion at one temperature of 843 ° C, then exposure to combustion for 2 minutes

o ^lf products at a temperature of 1010 C, 2-minute cooling.

This cycle was carried out for J6 hours.

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2. exposure to combustion products of a temperature of 954 ⁰ C for 3 minutes, then the action of combustion products 1121 ⁰ C for 2 minutes, cooling for 2 minutes. This cycle was run for 12 "hours.

After completing these tests, the bars were sandblasted, to remove coarse slag before taking the final weight measurements.

The results of this oxidation-erosion test obtained in comparison for the alloy according to Example 2 and the comparative samples are listed in the table below.

alloy Weight loss up to the oxidative
Attack elapsed
Time ^T 1 1.24 56 hours CS ₁ 1.61 20 hours CS ₂ 2.2 ^ 20 hours «

As can be seen from these tabular results, the alloy T- shows. very favorable oxidation resistance in this test compared to the alloys CS ₁ and CS ₂ *

Example 3.

Alloy molds (T ₂ and T ₅ ) according to the invention of the composition listed below in weight percent were processed into test bars of the same size as in Example 1 by the method described there. '.

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element alloy
nominally Tp 'alloy T ₂
In fact Alloy T-,
nominally 1812336
Alloy T ^,
actually ^ - 0.16 C. 0.105 0.18 0.105 0.11 2- 0.018 B. 0.015 0.019 0.015 0.01! - 0.09 Zr - 0.075 0.09 0.075 0.07 - 11.91 Cr - 15.0 14.18 12.0 11.83 - 3.98 Al - 4.0 4.03 4.0 3.77 - i, 8o Ti - 2.0 1.4 2.0 1.72 - 4.18 Ta - 4.0 3.8 4.0 3.98 - 1.63 Mon - 1.5 1.23 1.5 1.49 -15.73 Co - 10.0 9.90 15.0 15.37 -10.85 W. 5.0 5.14 10.0 9.92 Ni - rest rest rest rest

Comparative samples (alloys CS ^ and CS ^) became test bars processed of the same size (the alloy CS-, corresponds to U.S. Patent 3,310,399 and the alloy CS ^ is a cast alloy Udimet 700). The comparison samples had the following composition:

element

Zr Cr Al Ti Ta or Ta + Nb Mo Co Ni

alloy

Alloy CS ^

0.105 - o, 15th 0.10 0.015 - o, 02 0.03 0.07 - o, 075 8.0 15.0 6.0 4.25 1.0 3.25 4.3 ____ 6.0 5.0 10.0 18.5 rest rest

The test bars made from the alloys Tp and T ^ were then put together with the comparison bars made of the alloys CS ^ and

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CS ^ subjected to various tests. They were as follows Testing:

Test 1. In a sisothermal suIfidation erosion test, the Test bars and the comparative samples for 214 hours a temperature of 9 ^ 2 C the products of combustion of JP-5R nozzles exposed to 3.5 parts per million of a synthetic sea salt as described in Example 1 wearen. Figure 1 shows the weight loss versus time in this test.

Test 2. In a cyclic suIfidation erosion test (turbine ^ nenschaufeltest) test rods and comparison samples

placed in the flow path of combustion products of a JP-5R nozzle containing 3 * 5 parts per million synthetic Sea salt (composition as in Example 1) were added. The bars to be tested were 168 hours long subjected to the following cycle: exposure to products of combustion of a temperature of 84j5 C for 3 minutes, then exposure to combustion products a temperature of 1010 C for 2 minutes, subsequent cooling for 2 minutes.

Test 3 A cyclic sulphidation erosion test (turbine blade test) was carried out for 201 hours. The test rods and comparison samples were in the The flow path of the combustion products laid out by a JP-5R nozzle, containing 3.5 parts per million parts of a synbhetic Sea salt (composition as in example 1)

U /

were added. According to this test, it became the following

Cycle carried out:

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Action of Burn # ngsprodukten a temperature of 954 C for 3 minutes, then the action of combustion products at a temperature of 1121 ⁰ C for 2 minutes, then cooling for 2 minutes.

Figure 2 shows that for this test versus time applied weight loss.

Test 4. A cyclic sulphidation erosion test (turbine blade test) was carried out as in Test 2, wherein the total cycle time was 197 hours. The Pig. 3 shows weight loss versus time in this test.

Test 5 x 3s became a sulphidation-erosion test like Test 2 (Turbine blade test} carried out, the total duration of the cycles being 222 hours. FIG. 4 shows the weight loss versus time for this test.

Test 6. An isothermal oxidation-erosion test was carried out, in which the test rods and comparison samples 226 For hours at 1093 C the products of combustion JP-5R nozzle. Fig. 5 shows the weight loss as a function of time in this test and illustrates that the Le-

U 6/124 gi _chan g _es satisfactory values of oxidation resistance as compared with the known alloys having.

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Test 7 »A cyclical oxidation corrosion test (turbine blade test) was carried out carried out, the test rods and comparison samples in the cycle according to test 3 during a Total duration, of 120 hours in the flow path of the combustion products a JP-5R nozzle.

The results of Tests 1-7, expressed as weight loss, indicate (in g) of the various test rods and comparative samples, the following values:

Weight loss (grams )

1 ^T 2 ^T 3 CS ₃ CS ₄ test 2 -0.25 1.23 10.38 4.92 test 3 3.93 5.07 5.88 6.51 test 4th 3, -99 6.16 7.00 8.00 test 5. 2.73 2.31 6.79 4.95 test 6th 4.50 4.31 10.12 6.23 test 7th 0.96 1.70 0.98 1.65 test 1.19 1.11 0.82 1.50

Note that the original data for Tests 1-7 first give information to compare the behavior of the individual samples within each individual test. With everyone Comparison between the various tests must be considered be sure that the test types are different and have been carried out for different durations.

Tests 1-5 are different types of tests of sulfiding Erosion and the results of these tests clearly demonstrate the significantly superior suIfidation properties of the alloys according to the invention, in particular of alloy T. The tests 6

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7 and 7 show that the alloys Tp and T-, compared with the alloys CS-, and CS _{4, have} satisfactory oxidation properties.

As can be seen from the results shown in Figs. 1-4 is, the important general observation can be made that the alloys according to the invention with increased duration of exposure under suIfidierungsbedingungen a significantly increased Show resistance to suIfidation. It can also be seen that the behavior of the known alloys shows "kinks" in the curves of the behavior in that the known alloys after an initial period of time show a large increase in the rate of weight loss while the behavior curves of the alloys according to the invention neither so early no matter how steep they are.

Example. 4th

A melt of an alloy Th according to the invention was processed according to the method described in Example 1 to give test rods of the size specified there. The alloy had the following composition:
Element alloy T "

C 0.120 %

B 0.026 %

Zr 0.070 %

Cr. 11.82 %

Al 4.17 %

Ti 1.88 %

Ta 4.02 %

Mon 1.57 #

Co 15.65 % 909 8 25/1198

w 9.88 %

Ni. , Rest

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From the alloys according to US patent 3,310,399, CS ₁ -, and
Cast alloy Udimet 700, CSg were comparison samples in the form

made from test rods of the same size. The alloys have the following composition:

element Alloy CS, - Alloy CSg C. 0.150 % $ 0.10 B. 0.02 % 0.03 # Zr 0.07 % Cr 8.0 % ■ 15.0 % Al A Π ο /
O, U / ο 4.25 # Ti 1.0 % 3.25 ^ Ta + Nb 4.3 % Mon 6.0 % 5.0 ^ Co $ 10.0 18.5 % Ni. rest rest

Then a cyclic test of sulphidating erosion was carried out, where the test bars of the alloy Th and the comparative samples of the alloys CS, - and CSg during a total ' exposed to the combustion products of a JP-5R nozzle for a period of 216 hours according to the cycles described below were, which 3.5 parts per million · m; rush of synthetic Sea salt of a composition as in Example 1 were added.

Exposure to combustion products at 899 C for 3 minutes, then cooling for 2 minutes.

The results of this sulfidizing erosion test obtained by comparison gave T ^ for the alloy and the comparative samples CSc and CSg have the following values:

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alloy

real loss 1812336 G. 0.26 g 3.87 g 1.51 g Example 5

The melt rather alloy T, - according to the invention was after processed into test rods using the method described in Example 1. The alloy had the following composition:

Element alloy Tp-

C 0.10

B 0.016

Zr 0.063

Cr 11.80

Al. 3.98

Ti 1.62

T.a 3.50

Mo 1.40

Co * 14.80

W 9.30

Ni rest

Another sulfidizing erosion test was carried out with the test bars of alloy Tj- and the comparative samples of alloys CS ₁ - and CSg exposed to the combustion gases of a JP-5R nozzle for a total of 216 hours in accordance with the cycle described below 3.5 parts per million of a synthetic sea salt of a composition as in Example 1 was added. The following cycle was carried out:

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ο, 62 S. 3, 91 G 51 G

Action of combustion products at a temperature of 899 ^° C. for 3 minutes, then cooling for 2 minutes.

The comparative results of this sulfidizing erosion test for alloy T ₁ - and comparative samples CS ^ and CS ^ - were as follows:

Alloy weight loss

As can be seen from these comparative results of the two examples 4 and 5, the alloys Tj, and Tp show sulfiding properties which are significantly superior to _{the properties of the alloys CS P and CSg.}

Test devices that are suitable for carrying out the tests mentioned are in the "State-of-the-Art Survey on Hot Corrosion in Gas" Turbine Engines ", G.J. Danek, Jr., Naval Engineers Journal, 859 (1965) j and" Effects of Turbine Atmosphere on Sulphidation Corrosion ", M.J. Thereafterie, Jr., et al, ASME Reprint 67-GT-2.

From the tests mentioned and other analysis values, the general, common observation can terms of Sulfidierungseigenschäften t of the inventive alloys can be derived that a favorable interaction zwischen'Molybdän and chromium, however, there is a f harmful interaction between molybdenum and titanium or cobalt. Molybdenum should therefore be used in such proportions

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det, in which the beneficial effect is the harmful effect predominates and it is therefore preferred to limit the proportion of molybdenum to a maximum value of $ 1.5.

It has also been found that tantalum, together with tungsten, has a beneficial effect but, together with chromium, has an adverse effect on sulfidation. It is of course known that tantalum adversely affects the stability of the alloy. The favorable effectiveness of tantalum together with tungsten or titanium in the alloys according to the invention on the sulfidation properties, however, essentially outweighs the unfavorable effects which occur together with chromium, and it is therefore desirable to use tantalum in high amounts that are not possible are consistent with the requirements of alloy stability. Tantalum is therefore preferably in an amount of 4 wt - used.%. This presence of tantalum also appears to contribute significantly to good oxidative erosion properties of the alloy.

A computer was also used to do a retrospective multiple regression ^ft * lVyse

of data obtained in the corrosion test of the alloys according to the invention to obtain. For this purpose, the binary interactions between chromium, aluminum, molybdenum, tungsten, titanium, tantalum and Cobalt used as an independent variable. That way it was Develop the following equation showing the weight loss for 100 hours of exposure to sulfidation conditions describes:

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+ x _Mo (0.1O7x _Ti + o, 0109X _Co + o, 552)

+ X _w (-0.0793X _Ta + 0.0121X _Co -0.0520)

+ X _Ta (-0, i82X _T1 -0.648) + 0.0533X _Co

-0.0670x ^ + 0.176 g? ·

In this equation, X. means the atomic fraction of the component i.

Various binary interactions have been found to be important in weight loss after 100 hours. Both ™ important interactions for weight loss during 100 hours it concerns the following:

Cr: Ta (+) ¹ , Co (-), Mo (-); Cr (-) ²

Ti: Mo (+), Ta (-); Ti (-)

Ta: W (-); Ta (-)

Co: Mo (+), W (+); Co (+)

1.) (+) unfavorable interaction; (-) favorable interaction 2.) Effect of the element alone.

The following table was also obtained from computer analysis. In it means an interaction marked with (-) an adverse interaction and an interaction denoted by (-) a beneficial effect on weight loss.

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''"'!! I ¹ ' ¹ ''""" ■■■ ''"'3 !!! 11 !!!"! 1 !!! ¹ II !!! ¹¹ ?! ¹ * ¹ ?; ¹¹ " ^1: ·· ■ m

Weight loss after 100 hours. ■ * J ^ · "·

Cr χ Ta (+)

Cr χ Co (-)

Mo χ Tl (+)

Mo χ Co (+)

. W χ Ta (-)

W χ Co (+>.

■ Cr x Mo (-)

Ti χ Ta (-)

FIG. 6 shows the data of the above table in the form of a diagram. An upward arrow (f) means that an element X. with an increased proportion of a special element X. can be increased without reducing the resistance to sulfidation. A down arrow (^) indicates that if the amount of a specific element X. is increased, the amount of an element X. must be decreased if the resistance against sulfidation should not be reduced.

The values of the mechanical properties of the alloys according to the invention were also measured. For this purpose, test pieces in the form of rods with a length of 12.7 cm and a diameter of 1.6 cm were cast in the usual way, which had a narrowed central part with a diameter of 0.79 cm. The rods were thermally treated at 1080 ° C. for 4 hours in a hydrogen atmosphere, then cooled by air cooling to room temperature and processed so that they had a smooth surface. The following values of the average creep strength were obtained for the alloys T _{2 and T ^.} The percentage elongation was measured within the 2 hours of the break (CS ₀ are typical

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Alloys according to US Pat. No. 3,310,399).

Permanent
strength
ΓΠ ΓΠ
Hrs. 400 ^CS a
Hours. Stretching '
I ² 2, 7th CS
C ^f a 130 78ο 250 3.3 5, 8th 2, 0 540 120 660 10.0 4, 6th 4, 0 55 130 9 4, 0

Temp. ⁰ P (a) PSI (kg / cm ² )

i4oo (760) 85,000 (5,980)
I6OO (871) 40,000 (2,810)
I8OO (982) 24,000 (1,690)

1) Deformation within 2 hours to break.

From these average data it can be seen that alloys according to the invention have sufficient strength for use in Own plug-stuff gas turbine engines.

If one sees in beta that the alloys according to US Pat 3,310,399 are viewed as very high strength alloys, it is understandable that the strength values of the alloys according to the invention for use in aircraft gas turbine engines are satisfactory, although in some cases not as high as the values of the known alloys according to U.S. Patent 3,310,399.

From this description, the values obtained, the examples and tests show that alloys according to the invention are particularly suited for use under corrosive conditions high temperature, as in aircraft gas turbine engines, because they have superior suIfidation properties combined with satisfactory Have oxidation and strength properties.

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Claims (12)

Dr. Ing. E. BERKENFELD · Dipl.-Ing. H. BERKENFELD, Patentanwälte, Cologne Annex ■ File number for the entry dated December 2, 1968 Sch Name d. Note United Aircraft Corporation claims 1. Nickel alloy resistant to sulfidizing attack, characterized by the content of the following alloy components: 10-20 wt -.% Chromium, 2-13 weight-Jfc aluminum, 1 - 3 wt .- ^ titanium,
3.5-7.5 wt .- ^ O tantalum, 3 - 13 wt .- ^ tungsten, 1-3 wt -.% Of molybdenum, 5-20 wt .- ^ cobalt, 0 - 0. C £ wt .- $ boron, 0 - 0.1 wt .- $ zircon, 0 - 0.5 weight -fo carbon,
Refet essentially nickel. 2. Nickel alloy according to claim 1, characterized in that the molybdenum content has such a value that the interaction between molybdenum and chromium, which is beneficial for sulphidation, is harmful to sulphidation Effect of the interaction between molybdenum and titanium or cobalt predominates. 3 · nickel alloy according to claim 1 or 2, characterized in that the content of molybdenum is not more than 1.5 wt -.% Is. -23- 909825/1198 U 6/124 4. Nickel alloy according to one of claims 1-j5, characterized characterized in that the tantalum content has such a value that the interaction favorable to sulfidation between tantalum and tungsten or titanium, the interaction between tantalum and chromium which is unfavorable for sulfidation predominates. 5. Nickel alloy according to one of claims 1-4, characterized in that the content of tantalum about 4 wt -% by.. 6. Nickel alloy according to any one of claims 1-5 * characterized in that the chromium content has such a value that the reciprocal effect favorable to sulfidation between chromium and cobalt and molybdenum the interaction between chromium and tantalum which is unfavorable for sulfidation predominates. 7 · Nickel alloy according to one of claims 1-6, characterized characterized in that the titanium content has such a value that the interaction beneficial to sulfidation w between titanium and tantalum, the interaction between titanium and molybdenum, which is unfavorable for sulfidation, predominates. 8. Nickel alloy according to one of claims 1-7 * characterized by a content of the following alloy components: -24- 909825/1198 U 6/124 13 - 17 wt .- ^ chromium, 3.7 - 4.5 Weight % Aluminum, 1.5 - · 2.3 - weight % Titanium, 3.25 - 4.5 Weight - % Tantalum, 4/0 - 5.5 Weight % Tungsten, 1.0 - 1.75 Weight, - % Molybdenum, 9 - 11 Weight % Cobalt, 0.01 - 0.02 Weight - % Boron, 0.05 - 0.10 Weight, % Zircon, 0.1 - 0.15 Weight -. % Carbon, rest Nickel. 9. Nickel alloy according to one of claims 1-8, characterized by a content of the following alloy components: 14 - 15 wt .- ^ chromium, 3.7 to 4.3 wt -.% Aluminum, 1.7 - 2.0 wt .- ^ titanium, 3.5 - 4.25 wt .- $ tantalum, 4.5-5.5 wt .- ^ tungsten, 1.25 to 1.5 wt -.% Molybdenum, 9.5-10.5 wt .- ^ cobalt, 0.01 - 0.02 wt. ~ $ Boron, 0.05 - 0.10 wt .- ^ zircon, 0.10 - 0.15 wt .- # carbon, Remainder nickel. 10. Nickel alloy according to one of claims 1-9, characterized in that it consists essentially of the following 'components; about 15 wt -.% chromium, about 4 wt .- / o aluminum, about 2 wt -.% titanium, about 4 Genu-% tantalum, about 5 wt -.% tungsten, about 1.5 wt -.% of molybdenum, about 10 wt -.% cobalt, about OjCtJGew .- ^ boron, about 0.075 wt -.% zirconium, about 0.105 wt -.% carbon, balance nickel. 11. Nickel alloy according to one of claims 1-9, characterized in that it consists essentially of the following constituents: about 12 wt -% chromium, about 4 wt .- ^ aluminum. -25-909825 / 1198 U 6/124 % titanium, about 4 wt .- $ tantalum, about 10 wt .- ^ l of tungsten, about 1.5 percent; - - nium, about 2 wt..% molybdenum, about 15 weight -% cobalt, about 0.015 wt.. - ^ boron, about 0.075 wt .- ^ zirconium, about 0.105 wt -.% carbon, the remainder nickel, 12. Use of a nickel alloy according to any one of claims 1-11 as a material for parts that are at high temperature are exposed to the corrosive and erosive atmosphere of gas turbine engines. 909825/1198 U 6/124 Blank page