DE2107372A1 - Process for producing extremely impact-resistant coatings on substrates made from heat-resistant superalloys - Google Patents

Description

Process for the production of extremely impact-resistant coatings on subscribers made of heat-resistant super-alloy

struggles

The present invention relates to the nickel plating of refractory metal substrates by Packuugs cementing treatment, and in particular it relates to a method of producing an anti-heat corrosion protection resistant metal coating, according to which aas metal substrate is first nickel-plated to Jar on a to form diffusion-bonded nickel plating, and it then aluminized in a separate coating stage is used to produce a protective film with improved properties, the considerable amounts of nickel alumiriici enchälc, which coating markedly improved Impact strength on v / ice.

The latest development in metallurgical field has it has proven necessary to use heat-resistant alloys with high cobalt and / or high nickel

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held (which are sometimes referred to as "superalloys") to make available which have desirable properties in various high-temperature applications, e.g. in the manufacture of rotor blades and stator blades for gas turbines operated at high temperatures, - / υ for these machine parts Trouble-free operation, also aaim, requires aru if -you are exposed to temperatures of v; esentlien above 81 ° C (150 ° F) and even considerably above a temperature range at which selos; oat high temperature! ¹ eaten auatenitischen Odei · nickel steels Cnrorn a fraction ^ ner a Versenlechcerung JSI strength properties Sheep ter. can be expected.

Superalloys as such with nothing anaer ^ m do not always have a successful resistance to damage caused by heat corrosion in the case of abnormally increased! Temperatures shown. Corrosion-resistant coatings are therefore used as one of the means to help increase the resistance of the substrate to high-temperature corrosion, especially in modern jet engines / orvienaeten, complexly shaped machine parts / something that is known when handling and calibration can lead to a premature destruction of the ijehutzüoerzüge, which by nature tend to be brittle. As for the "superalloys" with cobalt as the gray metal, the coatings most commonly used for such applications consist of cobalt aluminides containing dispersions of carbides of the MC, MgC and M ₂ -zCg types. Coatings of this type give good resistance to oxidation, but oinu

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sen ζ-χ brittle for series production on assembly lines.

Attempts have also been made to develop a two-stage process for the independent deposition of nickel and aluminum on ^{! L} super-alloys "with cobalt as the base metal, including using a nickel-aluminum oxide packing (40 weight percent nickel powder and 00 weight percent aluminum oxide). , which contains a Halogenia accelerator (energizei-), for example 1/4 percent by weight of Anunoniuiiu ifluorid.These packs also did not bring about the transport or transfer of the roll with the desired success, because the vapors of the accelerator far rather tends to attack ax surface of Masciiinenuciiea,: ^^ 3 iiici-zel au: "er Paeku.ig abeiueii.

Zz is a method iran found vioraea, with its auxiliary = i; IAI ax Ubertx'aguiif-. aes nickels by packing decent on "3uperlegieru; ig £" -8ubs_: ate, like alloys Kii - K ^ aIt and iiicicel as base metal, under Ver · - meia-.Uig. which can bring about the formation of carbon-containing dissociation phases on the surface of the surface. While the invention i; xsbesondere on ''Superlegiex'Uügen"with cobalt as Gruiidiaetail is applicable se is cie uaneben for · λλ.- coating of alloys having nickel as Ji'unaii'.ötali, ax beispieis..eise 10 to J) C percent by weight Ghiv-door entr.aiten, where the deposited nickel aas chromium on the 3r-e: iz surface thins and so the formation outside 1 " ¹ WaLiItSiI chi '· ...! More haitiger. Embrittlement phases such as chromium carbide, nitride and the like prevented.

109882/1099 ORIGINAL BATHROOM

One object of the present invention is aahur under development a;: .-: procedure, uurcii which one extremely impact-resistant and heat-corrosion-resistant cover pull on "superalloys", e.g. those with Kcuait as Base metal and alloys with nickel as base metal and high chromium content.

Another item is to provide a "superalloy" substrate, e.g. the substrate of an "ouper alloy" with cobalt as the green metal, aer technology available to provide the one ductile, impact-resistant uij '; Has heat-corrosion-resistant coating on it "i is bound by diffusion.

These and other objects appear even more clearly The following description and the appended claims illustrated.

In a broad sense, the present invention relates to a method of creating a slack coating on a "superalloy" substrate by pack cementation in which a layer of a diffusion-bonded, sulfur-activatable transfer metal, such as nickel, is a first step in the course of the process final formation of an impact-resistant coating is produced. The improvement ;> e is in the fact that an article is produced from the ¹¹ superalloys mentioned, which contain a dissolved ketallic (solute metal), e.g. chromium larger than -; ie des llickels) i ^ t, rr; a-. '. the article in a in particles! ¹ ^ rm yi .. lie ^ eiice zernentierpackung, consisting mainly of aein ,, er.annueii ocriV / ei'oiaktivbaren Üoertragun ^ smetall in I'.isciiuri · ?; with eiiioi.-. inert, meltable material ( e.g. Alui..iniurrioA.yd)

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consists, embeds, the bed containing a small but effective amount of sulfur to the transfer or the transport (transfer) of said sulfur-activatable metal onto the substrate of said Item at an elevated diffusion coating temperature to effect., and one then the said pack uriJ uen articles embedded in it on a raised Difi'usionsbeschichtung Ternperatur heated so the Diffusion coating of that article with the transfer ^ unt- ^ metal, the implementation of the Do coating under the upright shark *, an oxygen

back in the pack, under the partial I

pressure is at which the oxidation of the sulfur to

Sch ..- eleldioxyd is prevented.

During the practical implementation of the packing ceremony The oxygen is kept at the desired partial pressure by adding a small but effective amount of an oxygen-scavenging metal (e.g. titanium) is added, in which the free BiI-ie for the oxide at least 115,000 calories

per gram atom of oxygen at about 25 ° C.

'■■ iivu winding used as a transfer metal, se should be the particulate nickel-plating packing, sin = composition J a: .i \ -; eisexi, which - expressed in percent by weight - consists of ^ - 60 % nickel, 1/8 - 1 # titanium, 0 , üG2 - ö, 1 55 sulfur and the remainder as v / eaeatlichen of an inert, schv / he, fusible material, for example a _o schvier fusible oxide, / ie aluminum jxyd, Magnesiumuxyd, u Siiiciumuioxyd the like, Derjteht. . A particularly suitable packing is composed .vi'uzuri-^ sriiäßig from about 40 jo nickel, 0.2% titanium, 0.02% ochv / efel and the balance substantially of aluminum UAjLk. After the production of the diffusion-bound nickel

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The substrate of the article is cleaned and coated the coated surface is then aluminized, creating an impact-resistant, nickel aluminide-containing Coating of improved ductility produced will.

As mentioned above, the way it works is both Applicable to "superalloys" with nickel as base metal as well as to those with cobalt as base metal. As an example of the alloys with nickel as the base metal, a typical alloy should be mentioned, aie the following components in amounts expressed in percent by weight are expressed, contains:

10 - 30 % chromium,

up to 20 f? one of the metals molybdenum and tungsten, up to 10 % one of the metals niobium and tantalum, up to 0.5 % carbon,

up to 6.5 % of one of the metals titanium and aluminum, the total amount of these metals not exceeding 10%,
up to 20 % cobalt,
up to 2 ° /> manganese,
up to 2 % silicon,

up to "; f: zirconium and as Res at least 45 % nickel.

"what the alloys with cobalt as base metal ag, so a typical alloy contains aie. following components in amounts expressed as a percentage by weight:

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10 υ it; ; 30 -} ;. Chr-; in, up to 1 ^ / j nickel, uiü su Ii) ^l /> iron, ols to 5 / niobium ^{,: ii <f to I!, * £} / 'V.'ulfrani,

dLj to 5 ¹ P titanium u ^ d or or aluminum,

ui5 to i i> zircon,

up to 1.5> o carbon,

bit to 1 ο'j er 2 f> Silicon,

OXG to 2 ',' Manganese and the remainder in, .ve ... public

rfeniirsteiis £ ^} \ ^l j> fi cobalt.

iiine commercially under the name "WI-32" available%

Lejiiei-unL ϊ "1 <- K ..bait ala Grundiaetall contains - in Gev; icntiipr«> zexvc disengaged -

v? ^: , -i3 / '- K-. hleiisi of f, 0.23 % manganese, 0.2. '^} ö silicon, «ii ρ chroiii,

11 ft tungsten, 2 jb niobium,

2> 6 iron and the remainder im -.jeoentlicheri Cobalt.

The . Optimal external method for nickel-plating the front - -

..ahnten alloy "WI-52 ^<: besteh .; · in the deposition of nickel at lu50 ° c - 1 ^"'C by means of a iCiiioetten uer Legiei'ung gefertitrten article, for example a Flügelaoschiiitues, in a partikelförrnige pack which 40 percent by weight electrolyte nickel from a mesh screen fineness. "On -200 meshes and όύ percent by weight aluminum with a mesh screen fineness of minus J2p Haschen

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contains, the (leniisch also .5 / 16 percent by weight Contains titanium and the sulfur content is 0.015 to 0.05 percent by weight. The primary source of the sulfur is the nickel powder. With the above-mentioned packing, nickel coatings with a thickness of up to 0.0506 mm are obtained (0.002 inch).

In the course of the investigation of the positive effect of sulfur or the sulfur-containing compounds as an aid in metal transport, it was observed that α en. Addition of a small but effective amount of sulfur flowers and sulfur compounds, ie NiS, Cr ^ S ^ and (NH _1. ) S, the amount and the sinring depth of the transferred nickel was increased. However, the presence of too much sulfur can result in extensive attack on the grain boundary carbide phases and in situ deposition of sulfur compounds. Therefore, the term "small but effective amount" is intended to encompass that amount of sulfur which results in the formation of the desired nickel coating and at the same time suppresses the deposition of sulfur-rich compounds, with the exception of the formation of chromium sulfide on the substrate surface, which is easily removed by honing with glass spheres. In order to achieve advantageous results, the amount of sulfur in the pack, be it intentionally added or be present in the packing materials used, e.g. nickel powder and / or aluminum oxide, should be in the order of magnitude of 0.002 to 0.1 percent by weight.

The sulfur is used in the formation of Zunaer and aer reaction with titanium (which acts as a "scavenger") and oxygen consumed. So can the reaction of sulfur with chromium the formation of various in the alloy substrate

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Chrornsulficiarteri result in naoen that are on the surface of the article following the deposition of the nickel. The implementation of the sulfur with the titanium some titanium sulfide may form in the pack to lead. The remaining oxygen in the pack can mix with the sulfur dioxide and the titanium to form titanium dioxide react. Which of these reactions take priority and the degree to which they take place, depends on the relative concentration of the elements in the pack.

In the nickel plating of the cobalt alloy listed above under the designation "VJI-52", a % sulfur content of the packing in the lower quantity range leads to a nickel zone in the substrate of 0.0127 mm (0.5 mils) thick with 2 to 10 % nickel diffused into the surface. In general, the lower the sulfur content in the pack in the small but effective quantity range, the weaker the nickel transport and the lower the depth of diffusion. Usually, a nickel zone is obtained on the alloy substrate containing up to 20 weight percent nickel as determined by microanalysis.

In the course of the normal sequence of the process, the TEI g Ie are as they are taken out of the Vernickelungspackung, covered with bright / n scale, which is removed by honing with glass beads at low pressure. The scale consists of certain phases of chromium sulfide with enclosed powder from the pack, whereby the composition of the chromium sulfide can consist of sulfides of the formulas Cr ₂ S- to Cr'p-Sg. The average thickness of the scale is usually 0.00 (6 mm (0.3 mils),

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and the thickness increases with the addition of sulfur and eggs Nickeltrarisport.

It is important, for example, that the partial return of oxygen in the pack is kept at a value below the value at which the oxidation of sulfur is essentially prevented. As has been determined, an amount of titanium of about 3/16 % is particularly advantageous in order to ensure an improved nickel transfer during the course of the nickel-plating process while at the same time reducing the damage caused by oxidation to a minimum. Notwithstanding this, other oxygen scavengers can also be used, provided that the free energy of formation of the oxide is at least 115,000 calories per gram atom of oxygen, as already mentioned above, the transfer of the back from the packing to the alloy substrate is impaired, unless care is taken ..- that the partial pressure of oxygen in the pack is kept at the desired low value.; irci. Such an impairment can occur if there is too little titanium in the dex packing to suppress the formation of sulfur dioxide and even of chromium oxide on the alloy substrate. If, for example, there is no titanium in the packing, the consequence of this is that there is no transfer of nickel and the Sudstrat is coated with a strong layer of oxidation. Another method of keeping the oxygen partial pressure at the desired low value consists in flushing away the oxygen contained in the package with the aid of an essentially oxygen-free inert gas such as argon. In general, it can be said that when titanium is used as an oxygen scavenger, its amount in the pack can be 1/8 to 1/8. A typical packing suitable for treating the alloy "WI-52",

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j-oscent example from ^ O fo nickel powder, the packing Cii.isch £ 3 / l6 ■ / 'titanium and 0.015 to 0.05 ¹ A sulfur and Tixs Resc a substantially inert, hard fusible oxide, such as alumina, . A particularly recommended quantity range for titanium is between 3/16 and 1/2 %.

To illustrate the various "superalloys", which can be provided with the coating according to the teaching of the present invention are those in Alloy J compiled in the table below

types are listed for example. ™

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Table 1

Designation
tion of the
alloy Chemical composition in eight percent C. Cr Ni Co Mon W. Nb Pe Ti Al B. Zr other Mar-M-509 0.55-
0.65 23-
24.5 9-11 rest 6.5-
7.5 Max.
2.0 0.15-
0.25 Max.
0.01 0.1-
0.6 3-4 days SM-. ? 02 0.05 21.3 rest 10.0 0.005 0.20 9.0 Ta AiResisc
213 0.33 19.0 Max. rest 4.5 Ta + Nb
7.5 Max.
0.5 4.3 0.13 0.13 υ L-605 0.1 20.0 10.0 rest 13th - 1.5 mn
0.3 Si 0.43 <: l, o 11.0 2.0 2.0 0.25 Mn
0.25 Si X- 10 0.5 25.5 10.5 rest i ', 3 - 0.75 Mn
0.75 Si Uoirnet 500 0.0b L-., 0 rest Iu, 3 4.0 2.9 2.9 0.00ό 0.05 --- | r <ia r- M- 4; 52 0.15 Ib, · '» rest 19.7 3.0 i, fc 4, 4 2.9 0.013 0.03 2.2 Ta IN-713 C 0.12 12,.; rest '!,:.? - 2.0 0, b 6.1 0.012 0.10 Hastelioy X 0.1 O .- ■ .- ¹ N
<- "-, v. · 1.3 °, o 0.6 18.3 - 0.3 Mn
0.5 Si Incoiiei 6 ^ 0 0.04 13.8 Re ^ t - 7.2 - 0.2 Mn
0.2 Si

■ «J co

When nickel-plating the alloys "SM-3O2" and "AIResist 215" for PO hours at 1050 ° C ± 14 ° C (1925 ° F - 25 °) in a pack containing 40 % electrolyte nickel powder (mesh sieve fineness minus 200 Mesh), 3/16 $ titanium, 0.03 % sulfur and the remainder essentially contains aluminum oxide (mesh screen fineness minus 325 meshes), a deposited nickel zone was obtained, the nickel content of which was 20 to 22 percent by weight according to a microanalysis.

Following the nickel-plating of the alloys compiled in Table 1, the nickel-plated alloys are then packaged in a prereacted pack containing - expressed in percent by weight - 20 % chromium, 3 % aluminum, 1/4 ^a ß> NH ₂ , FHP and as The remainder essentially contained aluminum oxide (hash sieve fineness minus 325 meshes), aluminized in order to obtain a corrosion-resistant coating of considerably improved impact resistance. In the case of alloys that contain cobalt as the base metal,

generated
consists of _A Uberzug 0.051 to 0.064 mm (0.002 ^-:

0.0025 inch) thickness of nickel-cobalt-aluminides, which contain chromium in solid solution.

In the case of the alloy "Hastelloy X" (which consists of 0.1 % carbon, 22 % chromium, 1.5 % cobalt, 9 % molybdenum, 0.6 % J tungsten, 18.5 % iron, 0.5 % manganese, 0.5 % silicon and the remainder consists essentially of nickel) the substrate is nickel-plated in an analogous manner for about 10 hours at a temperature of 1050 ° C - 14 ° C (1925 ^O F t 25 ° F) in a pack that - Expressed in percent by weight - 20 % electrolyte nickel powder (mesh screen fineness minus 200 meshes), 0.3 ^ titanium, 0.02 % Schv / efel and the remainder essentially aluminum oxide with a mesh screen fineness of minus

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See contains, whereupon the surface of the alloy substrate is cleaned by honing with glass balls and then aluminized for 20 to 30 hours at 103O ⁰ C - 14 ⁰ C (1900 ⁰ P - 25 ⁰ P) in the above-mentioned pre-reacted pack to make it corrosion-resistant Nickel aluminide coating 0.064 to 0.076 mm (0.0025 OOO3 inches) thick which is extremely shock resistant and resistant to chipping.

The treatment in the nickel-plating package causes a depletion of chromium in the substrate, which leads to the formation a tough aluminide coating during the second diffusion bond is to be considered. The improved Toughness of the coating compared to the more brittle coatings on such alloys commonly used is evident in the less chromium-rich phases in the coating and the absence attributable to any porosity at the coating-substrate interface.

In the case of the alloy with the trade name "WI-52" the improved impact resistance coating has a strength of at least 17 pounds. Inches on opposite a value of 1/4 pound. Inch, which is an aluminide coating produced in a conventional manner in a single step having.

A simple test that has been developed to determine the stress and temperature conditions of real Turbine metal split during the operation of the · Trie Dv / erke to simulate consists of a simple bending load test, in which the load is applied to a test stick provided with the coating, which is

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end to the other end of the rod is exposed to an extending temperature gradient, which comes about with the help of a bundled acetylene / oxygen flame, which is aimed at the center of the test rod, the heat can be distributed to the opposite rod ends. Each test piece is cooled down in a 10 minute period from the maximum temperature of, for example, 10905 ° C (2000 ° P) to the temperature at which the metal has assumed a dark color. While the test sample is being cooled, the load consisting of a simple beam is raised and dropped three times to reproduce damage from collision with a foreign object during operation. The results have shown that there is an improvement in the ratio of at least 3: 1 compared to the above-mentioned coating applied in a conventional manner by veralizing, according to the teaching of νjrlyingjen ßrfirijung. "In, · · In the conventional, applied in one stage aluminide a Abspaner * and Abclattern occurred after 45 test cycles oe ^ plating - -.,:., However, the after ¹ Jc, - aer Lenre present invention applied veruesdei'tt ü '. wore still after 2 3ϋ>Τι;: _- "cycles was intact.

Like cue: i ersännt, kanu uie Vemic'-ieluagr.packung - in Gewicr.tspr :: sc-, iw a .sgeaiickt - [;. to b \ jy, liickelbulver, I / o üii 1 .. "-xltaii, C, COi to 0,1,". ' och.v-afei unu contain as the remainder an inert, black, fusible material, e.g. a particulate, difficult-to-melt oxide, such as Al-O, MgO, 3iG, and the like, although the respective cornpouenia are in larger quantities on the outside ange \ .eii- <ct v / eroen fiünneri.

To be felt as examples of oxygen scavengers ^ iriu Thjr-ia..i, cerium, yttrium and the other rare earth metals.

The y -.- nickel-plating temperature can be oil: '-, ois 1GJ3 ° C ° 2000 "! ·) For a duration of 5 to 40 hours.

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A cement pack that can be used in the aluminizing stage consists of 10 to J> 0% of a buffer metal (e.g. chromium ^ 1 - 5 % aluminum, a small but effective amount of a halide accelerator (energizer), e.g. 1/4 % NH ^ FHF (e.g. 1/8 - 1 % accelerator) and the remainder of an inert, difficult-to-melt material as listed above. The buffer metal helps to control the transport and deposition of the aluminum. Examples of other buffer metals are . nickel, iron UNU to lead cobalt Generally speaking, are mixed together, the package and at elevated temperatures of, for example ^ A to 1121 ⁰ C (1750-2050 ⁰ F) 1 to 20 gradually reacts pre-before used for the coating formation viira, and The nickel-plated article is then veralurninier-t for 1 to JO hours oei 'y ^ h Dir-, ° C (1750 - 2O5O ^{C F).}

For closer ver-ansciiaulicnuiig uer jlrl'jncjuri ^ .- / ird dao the following example is given:

Example l

Ξ, ΐϊ. 'ir-agflächenprofil aus ^ ir.er L- ^ i-.ierung ("WI-5L ^J "), which from

0.43 f ₃ KohleriotuiT, 0.25 ^c / j manganese, C, kj% silicon, 21>; Chrome, 11 Ji rtolfram,.

2 fj niobium,

2 % iron and the remainder essentially a υ cobalt

oe ^ teht, a nickel'O -.g .'-

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4O% electrolyte nickel powder (mesh ^{screen fineness.:}

minus 200 stitches), '"

0.2 i> titanium powder,

0.02 % sulfur and the remainder essentially · ':

Contains aluminum oxide (mesh screen fineness minus 525 meshes). The muffle is sealed with a low-melting silicate glass mass and then in a muffle furnace to a temperature of 1050 ⁰ C ± 14 ° C - heated and held for 30 hours at temperature (1925 ° F 25 ° P). The muffle is then cooled to room temperature and *

the airfoil section is cleaned by honing with glass balls under low pressure in order to protect the. Remove any chromium sulfide scale from the surface. * '. 'There is obtained a nickel diffused layer <' · a 0.051 mm (0.002 inch) thick, enriched zone Open f \ i '\ exhibits containing 20% nickel. ΐ ~ Τ

After cleaning the wing element this is;

Element embedded in an analogous way in an aluminizing packing, which - expressed in percent by weight 20 ^c fo chromium (powder of a mesh screen fineness

of minus 100 meshes) as a buffering agent, 3 % aluminum powder (mesh screen fineness minus 325 meshes),

1/4 % NH ^ PHF and the remainder essentially i

Aluminum oxide of a mesh screen fineness of minus

325 meshes

contains. The aluminizing was carried out for 20 hours in a sealed muffle to create an extremely tough mixed nickel-cobalt-aluminide coating, which Chr.-ra in solid solution contains.

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Claims (1)

Claims Process for the production of extremely impact-resistant coatings by cementing packages on a substrate an article made of a heat-resistant "superalloy" by diffusing in Nickel in the substrate as the first stage of the final formation, the aforementioned impact-resistant coating, characterized in that one made of a chromium-containing "superalloy" existing articles in a particulate cement package consisting essentially of nickel powder in a mixture with an inert, difficult to melt material, embeds, the bed for the purpose of bringing about the transition of said nickel to the substrate of said article at an elevated diffusion coating formation temperature contains a small but effective amount of sulfur, one then said package with the article embedded therein to an elevated diffusion coating formation temperature heated so as to effect the diffusion coating of said article with nickel, and one while the coating is being carried out, the oxygen in said pack is at a partial pressure which is below the pressure at which the oxidation of sulfur to sulfur dioxide is essentially prevented will. 2. The method according to claim 1, characterized in that the oxygen is thereby at the desired partial pressure is held that one of the pack mentioned a small but effective amount a.- .; oxygen aoi'an- 109? 82/1099 natural metal, in which the free energy of formation of the oxide is at least 115,000 calories per Gram atom of oxygen. 3. The method according to claim 2, characterized in that that the oxygen-scavenging metal consists of titanium. H. A method according to claim J5, characterized in that the pack renegotiation bed consists of
'j to oü ?? Nickel,
1/8 old 1 ϊ, titanium,
0.001- oits 0.1; ·) sulfur and the remainder essentially from the inert, he; i..er fusible material 3. Method gei..äi claim 4, caaurc ;, characterized, ialS the Beti
+ 0 % nickel, L, 2 y> Ti tau, \ 'i ocnvioi'el and as a hest in the. public out tent. L. Ζ-; rfanre .: i _; : eiiiätc. Aiispi'uch '♦, o;.: -: /. "' CJi ^ .a .- .; zti.jhnet, <.. ai? Ι ;;. Aiit; -c:; lu :? ai the gener. : ..: of the .. diffuaions-
- 'ebunderien' -iickelüberzu £ es da.i babstrat Jes ni-tikels united uiicj the exaggerated 01. erf lache.; aa ;. veralu- "iiniert ./ira, in order to thereby -.- lAe.i äuiKer-ct beat and gea Aoblättein uestän - :: i _? c /. L \ erzu £., j er Nic.cel- -iv '. ininid e ^ thäli, to generate ... 109882/1099 7. The method according to claim 6, characterized in that the article provided with the nickel coating is aluminumized in such a way that it is embedded in a cement pack, "which - expressed in percent by weight - 10 to 30 ^ chromium, 1 to 5 % aluminum, a small but effective amount of a halide compound inert? contains faster and the remainder a particulate, _A difficultly fusible material, and then aluminizing the said article for 1 to j%) hours at a temperature of 95 ^ to 1121 ° C (1750-2050 ° F). 8. The method according to claims 1 to 7, characterized in, that as "superalloy" either a representative of the group of alloys with cobalt as Base metal is chosen, which - expressed in percent by weight - contain 10 to 30 % chromium, up to 15 % nickel, up to 15 % iron, up to 5 % niobium, up to 15 % tungsten, up to 5 % titanium and / or aluminum, up to 1 % zirconium, up to 1.5 % carbon, up to 1 or 2 % silicon, up to about 2 % manganese and the remainder essentially 45 % cobalt or a representative of the group of alloys with nickel as the green metal, which contain - expressed in percent by weight 109882/1099 10 to 30 % chromium, up to 20 % of one of the metals tungsten and molybdenum, up to 10 % of one of the metals niobium and tantalum, up to 0.5 # carbon, up to 6.5 % of one of the metals titanium and aluminum, whereby the total amount of titanium and aluminum does not exceed a value of 10%, up to 20 % cobalt, up to 2 % manganese, up to 2 % silicon, up to 0.1 % boron, up to $ 1 zircon and the rest at least 45 % nickel. 9. Product of manufacture, characterized in that it is claimed according to one of the claims 1 to 8 Process has been established. '.' 39882/1099