US20200080184A1 - Method of manufacturing an oxidation-resistant component of a molybdenum base alloy - Google Patents

Method of manufacturing an oxidation-resistant component of a molybdenum base alloy Download PDF

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Publication number
US20200080184A1
US20200080184A1 US16/564,019 US201916564019A US2020080184A1 US 20200080184 A1 US20200080184 A1 US 20200080184A1 US 201916564019 A US201916564019 A US 201916564019A US 2020080184 A1 US2020080184 A1 US 2020080184A1
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Prior art keywords
slip
semifinished part
powder
component
silicon
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Abandoned
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US16/564,019
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English (en)
Inventor
Heinrich Walter
Philipp Utz
Martin FROMMHERZ
Ludwig Hilser
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MTU Aero Engines AG
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MTU Aero Engines AG
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Assigned to MTU Aero Engines AG reassignment MTU Aero Engines AG ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Frommherz, Martin, Hilser, Ludwig, Utz, Philipp, WALTER, HEINRICH
Publication of US20200080184A1 publication Critical patent/US20200080184A1/en
Abandoned legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/18—Solid state diffusion of only metal elements or silicon into metallic material surfaces using liquids, e.g. salt baths, liquid suspensions
    • C23C10/20—Solid state diffusion of only metal elements or silicon into metallic material surfaces using liquids, e.g. salt baths, liquid suspensions only one element being diffused
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/04—Alloys based on tungsten or molybdenum
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/06—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases
    • C23C10/08—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases only one element being diffused
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/60—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C12/00—Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces

Definitions

  • the present invention relates to a method of improving the high-temperature oxidation resistance of molybdenum-based alloys or molybdenum base alloys.
  • the present invention relates to a correspondingly produced component composed of a molybdenum base alloy which can, in particular, be a component of a turbomachine and in particular an aircraft engine.
  • Molybdenum and its alloys are interesting materials for high-temperature applications because of the high melting point and the good corrosion resistance.
  • the present invention provides a method having the features of the independent method claim.
  • a component having the features of the independent product claim is likewise provided by the present invention.
  • Advantageous embodiments are subject matter of the dependent claims.
  • the invention proposes applying the silicon via either a liquid or a gaseous phase to an appropriate region to be protected against high-temperature oxidation on a molybdenum-based semifinished part in order to produce a correspondingly protected component. Accordingly, the method of the invention encompasses not only the provision of a molybdenum-based semifinished part but also the provision of either a silicon-containing slip or a silicon-containing powder.
  • the silicon-containing slip is applied to the regions of the semifinished part which are to be protected against high-temperature oxidation, with diffusion annealing subsequently being carried out so that silicon can diffuse from the slip into at least the regions close to the surface of the molybdenum-based semifinished part in order to provide silicon there for formation of a silicon oxide layer.
  • the silicon-containing powder is provided in order to introduce silicon into the region close to the surface of the semifinished part via the gas phase.
  • the silicon-containing powder is arranged at a distance from the semifinished part to be protected, so that the silicon can diffuse into the surface of the semifinished part in a diffusion heat treatment on the semifinished part with the silicon-containing powder.
  • the semifinished part prepared in this way can additionally be conditioned by means of an oxidation treatment, so that a thin, slowly growing silicon oxide layer which protects the component against further oxidation is formed on the component.
  • the conditioning can be carried out by means of an oxidation treatment at a temperature of more than about 900° C., in particular in the temperature range from about 1000° C. to about 1400° C., in particular at about 1380° C., for a time of up to about 2 to 100 hours, preferably from about 10 to 15 hours, in particular about 12 hours.
  • Heating to the treatment temperature and cooling from the treatment temperature can be carried out slowly, in particular at a heating and/or cooling rate of less than or equal to about 10 K/min.
  • Conditioning can be carried out in ambient air or under specifically prepared oxygen-containing gases.
  • semifinished part it is possible to use, for example, a semifinished part composed of Mo alloys with Si and/or titanium and/or boron and/or Fe.
  • the proportion of Si can here be in the range from about 5 to about 25 at. %, while Ti can be present in the alloy in an amount in the range from 0 to about 30 at. % and B can be present in an amount in the range from about 5 to about 15 at. %.
  • such an Mo base alloy can comprise up to about 5 at. % of iron, with any combinations of the alloying elements being possible while the respective balance is formed by Mo.
  • the enrichment of at least subregions of the surfaces of the semifinished part with silicon via application of a slip or via the gas phase is, in the present invention, carried out in particular directly on the above-described materials of the semifinished parts, so that no additional intermediate layers on the surface of the semifinished part are necessary.
  • halogens can be present in the silicon-containing powder in order to improve the diffusion of the silicon into the semifinished part.
  • halogen-containing compounds it is possible to use NH 4 F, NH 4 Cl or NaF.
  • the silicon-containing powder for transferring the silicon via the gas phase into the semifinished part can contain additional constituents in addition to the silicon powder.
  • additional constituents of the powder can serve as filler material and prevent caking of the powder.
  • additional constituents can influence the total amount of silicon and control the gas-phase activity of the silicon.
  • the silicon-containing powder for transferring the silicon via the gas phase into the semifinished part can preferably be arranged in a ceramic vessel underneath the semifinished part during the diffusion heat treatment.
  • the diffusion heat treatment of the semifinished part with the silicon-containing powder arranged at a distance can be carried out at a temperature of more than about 900° C., in particular in the temperature range from about 1100° C. to about 1300° C.
  • the hold time at the appropriate heat treatment temperature can be in the range from about 0.5 to 5 hours and preferably in the range from about 1 to 2 hours.
  • the semifinished part can be arranged together with the powder in a protective gas atmosphere, for example an argon atmosphere or a hydrogen atmosphere.
  • the slip can comprise silicon-containing powder or silicon powder and a solvent and a binder.
  • Possible solvents are, for example, water, alcohols or alcoholic solvents or liquid-organic solvents.
  • binders it is possible to use, for example, polyvinyl alcohols or resins.
  • the slip can contain further constituents such as Mo, W, B, Ta, Cr, Fe, Ti and alloys thereof, with these components either being able to be present as alloying constituents in the silicon-containing powder or being able to be added as separate powder particles.
  • constituents for controlling the silicon activity or matching the coefficients of thermal expansion of the layer produced and of the substrate or semifinished part can be added.
  • the slip can contain further constituents in the form of oxide, carbide or nitride particles which can be incorporated into a silicon oxide layer on the component in order to reduce the viscosity of the oxide layer and prevent running-off of the oxide layer at high use temperatures of the component.
  • the slip can contain aluminum oxide, zirconium oxide, yttrium oxide, hafnium oxide, neodymium oxide, silicon carbide and/or silicon nitride.
  • the powder particles can be present with an average particle size or a maximum particle size of from about 0.5 ⁇ m to about 100 ⁇ m and in particular about 1-60 ⁇ m in the slip.
  • the slip can be applied to the semifinished part by dipping, spraying, printing and in particular by screenprinting or template printing.
  • the diffusion annealing of the semifinished part with the applied slip can be carried out at temperatures above about 900° C. and in particular at temperatures of from about 1000° C. to about 1400° C.
  • the hold time at the annealing temperature can be in the range from about 1 to 3 hours and in particular up to about 2 hours.
  • indications of position are given in the present description, for example bottom, top or the like, these indications are based on the usual position during use in the gravitational system of the Earth, so that top indicates the position remote from the Earth's surface, while bottom is localized in the direction toward the Earth's surface.
  • a molybdenum-based alloy or molybdenum base alloy is an alloy whose largest constituent is molybdenum. Alloys in which one alloying component is present in an equal or similar proportion to that of molybdenum in the alloy are also intended to be included under the term molybdenum-based alloy or molybdenum base alloy. Accordingly, the term molybdenum-based alloys or molybdenum base alloys refers to alloys which comprise more than 50 percent by weight or atom percent of molybdenum.
  • high-temperature oxidation is an oxidation at temperatures which are higher than normal ambient temperatures and in particular higher than about 500° C., preferably higher than about 1000° C.
  • FIG. 1 a depiction of an arrangement for producing an Si-containing outer layer via the gas phase
  • FIG. 2 in subfigures a) and b), a depiction of the application of a slip to a semifinished part
  • FIG. 3 a depiction of a cross section through the outer region of a semifinished part which has been treated as shown in FIG. 1 or FIG. 2 , and in
  • FIG. 4 a depiction of a cross section through the outer region of the semifinished part of FIG. 2 after conditioning.
  • molybdenum a molybdenum alloy comprising 9 at. % of silicon and 8 at. % of boron with molybdenum as balance and also a molybdenum alloy comprising 27 at. % of titanium, 13.5 at. % of silicon, 5.5 at. % of boron and 1 at. % of iron with molybdenum as balance have been used as materials of the treated semifinished parts.
  • oxides such as La 2 O 3 can additionally be added to the material.
  • FIG. 1 shows an example of an arrangement for producing an Si-containing outer layer in a semifinished part 4 via the gas phase.
  • a vessel 1 for example made of aluminum oxide, which has a lid 2 and in which a silicon powder containing NH 4 F is present is provided.
  • the semifinished part 4 to be treated is located above the silicon powder so that when the vessel 1 is heated to a temperature of about 1190° C. in an argon atmosphere for a time of 2 hours, silicon can diffuse into the outer layer of the semifinished part 4 .
  • the diffusion heat treatment results in formation of an outer region of the semifinished part 4 as is shown in cross section in FIG. 3 .
  • a silicide layer 6 has been formed on top of the base material 5 by inward diffusion of silicon.
  • the semifinished part 4 is aged in air at a temperature of about 1400° C. for 8 hours so that a silicate layer 8 is formed on top of the silicide layer 6 by oxidation of the silicon, while an interdiffusion layer 7 which serves as silicon reservoir is formed between the silicide layer 6 and the base material.
  • This structure of the outer region is shown in FIG. 4 .
  • FIG. 2 shows, in the subfigures a) and b), an alternative working example in which the silicide layer 6 is formed by a slip 12 , which is present in a vessel 10 , being applied by means of a brush 11 to the semifinished part 4 and drying at about 50° C. subsequently being carried out.
  • a heat treatment under reduced pressure at 1400° C. for 1 hour is subsequently carried out so that silicon can once again penetrate into the base material 5 of the semifinished part 4 and a silicide layer 6 , as depicted in FIG. 3 , is formed.
  • the semifinished part 4 which has been enriched with silicon is appropriately conditioned so that formation of the outer region as depicted in FIG. 4 and as has been described above occurs.
  • the enrichment with silicon by means of the slip process can of course be applied to all molybdenum-containing materials in the same way as the silicon gas-phase coating procedure.
  • the slip is formed by a silicon powder having a particle size of 45 ⁇ m in an aqueous solution, with additional components, for example boron powder having a particle size of 35 ⁇ m or the like, being able to be added to the slip solution.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Powder Metallurgy (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
US16/564,019 2018-09-10 2019-09-09 Method of manufacturing an oxidation-resistant component of a molybdenum base alloy Abandoned US20200080184A1 (en)

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DE102018215313.2 2018-09-10
DE102018215313.2A DE102018215313A1 (de) 2018-09-10 2018-09-10 Verfahren zur Herstellung eines oxidationsbeständigen Bauteils aus einer Molybdän-Basislegierung

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210292882A1 (en) * 2018-08-07 2021-09-23 Commissariat A L'energie Atomique Et Aux Energies Alternatives Coating for refractory alloy part
US12618126B2 (en) 2023-06-27 2026-05-05 Wisconsin Alumni Research Foundation Chromium-molybdenum-aluminum alloys with oxidation-resistance imparted by thermal pre-treatment

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102019218784A1 (de) * 2019-12-03 2021-06-10 MTU Aero Engines AG Verfahren zur herstellung eines oxidationsbeständigen bauteils aus einer legierung auf basis eines refraktärmetalls

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GB709806A (en) * 1950-12-08 1954-06-02 Gen Electric Co Ltd Improvements in or relating to electrical resistance heating elements
US2865088A (en) * 1952-10-16 1958-12-23 Fansteel Metallurgical Corp Refractory metal bodies
WO1992000256A2 (en) * 1990-06-25 1992-01-09 Lanxide Technology Company, Lp Composite bodies and methods for making same
US6340398B1 (en) * 2000-04-04 2002-01-22 The United States Of America As Represented By The Secretary Of The Air Force Oxidation protective coating for Mo-Si-B alloys
US7005191B2 (en) * 2003-05-01 2006-02-28 Wisconsin Alumni Research Foundation Oxidation resistant coatings for ultra high temperature transition metals and transition metal alloys
DE10347363A1 (de) * 2003-10-11 2005-05-12 Mtu Aero Engines Gmbh Verfahren zur lokalen Alitierung, Silizierung oder Chromierung von metallischen Bauteilen
EP1900842A1 (de) * 2006-09-11 2008-03-19 Difcon GmbH Pack auf Zwischenschicht
EP2980263A1 (de) * 2014-07-30 2016-02-03 MTU Aero Engines GmbH Bauteil aus einer Molybdän-Legierung und Verfahren zu seiner Herstellung
DE102016202872A1 (de) * 2016-02-24 2017-08-24 MTU Aero Engines AG Bauteil aus einer Molybdän-Legierung und Verfahren zur Ausbildung einer Oxidationsschutzschicht hierfür
CN107523785A (zh) * 2016-06-21 2017-12-29 张家港市思杰五金工具有限公司 钼基合金表面抗氧化涂层及其制备方法
DE102016224546A1 (de) * 2016-12-09 2018-06-14 MTU Aero Engines AG HEIßGASKORROSIONS - UND OXIDATIONSSCHUTZSCHICHT FÜR TIAL-LEGIERUNGEN

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210292882A1 (en) * 2018-08-07 2021-09-23 Commissariat A L'energie Atomique Et Aux Energies Alternatives Coating for refractory alloy part
US11542586B2 (en) * 2018-08-07 2023-01-03 Commissariat A L'energie Atomique Et Aux Energies Alternatives Coating for refractory alloy part
US12618126B2 (en) 2023-06-27 2026-05-05 Wisconsin Alumni Research Foundation Chromium-molybdenum-aluminum alloys with oxidation-resistance imparted by thermal pre-treatment

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EP3620548A1 (de) 2020-03-11
DE102018215313A1 (de) 2020-03-12

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