US3489534A - Lightweight metallic structure - Google Patents

Lightweight metallic structure Download PDF

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Publication number
US3489534A
US3489534A US606943A US3489534DA US3489534A US 3489534 A US3489534 A US 3489534A US 606943 A US606943 A US 606943A US 3489534D A US3489534D A US 3489534DA US 3489534 A US3489534 A US 3489534A
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United States
Prior art keywords
wires
core
wire
mesh
shell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US606943A
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English (en)
Inventor
Moses A Levinstein
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
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Filing date
Publication date
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Publication of US3489534A publication Critical patent/US3489534A/en
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
    • C22C47/02—Pretreatment of the fibres or filaments
    • C22C47/06—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element
    • C22C47/062—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element from wires or filaments only
    • C22C47/068—Aligning wires
    • 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
    • B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
    • B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
    • C22C47/20—Making alloys containing metallic or non-metallic fibres or filaments by subjecting to pressure and heat an assembly comprising at least one metal layer or sheet and one layer of fibres or filaments
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/08—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator
    • F01D11/12—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between rotor blade tips and stator using a rubstrip, e.g. erodible. deformable or resiliently-biased part
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L9/00—Rigid pipes
    • F16L9/02—Rigid pipes of metal
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T50/00—Aeronautics or air transport
    • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12424—Mass of only fibers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12444—Embodying fibers interengaged or between layers [e.g., paper, etc.]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12729—Group IIA metal-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12736—Al-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12931—Co-, Fe-, or Ni-base components, alternative to each other

Definitions

  • a lightweight metallic structure such as a shroud, includes hollow wires bonded together.
  • the Wires are an alloy including at least one of aluminum, magnesium or their alloys and at least one of iron, nickel, cobalt or their alloys.
  • This invention relates to lightweight metallic structures and, more particularly to such a structure including members such as filaments, strands or wires of metal bonded together.
  • mesh Lightweight mesh, fabric or metal wool structures, hereafter called mesh, employing strands, wires or filaments, hereafter called wires, held to or bonded with one another, alone or as a support for other members, use such wires in solid form in uniform or random arrangements.
  • wires can be bonded together by welding, brazing and the like.
  • One use for such a structure is as a gas seal held between successive stages of an axial flow turbine.
  • layers of mesh bonded to holding members are located opposite the tips of blading members.
  • filler materials are disposed between wires. Because of the variety of metals available for the wires and variety of available filler or bonding material, abradbility, temperature resistance, oxidation resistance and the like can be selected for the mesh. However, because commerically avaiable fine wires are solid, the density of the material is greater than that which would be most desirable, particularly for use in an aircraft gas turbine where weight is an important factor.
  • Another object is to provide an improved, lightweight gas turbine abradable shroud.
  • FIG. 1 is a sectional isometric view of a wire having a solid metallic core and a continuous metallic shell prior to processing;
  • FIG. 2 is a sectional isometric view of the wire of FIG. 1 after processing
  • FIG. 3 is a partially sectional isometric view of a shroud including the structure of the present invention.
  • FIG. 4 is a more detailed sectional view of a shroud of the present invention including stacked unwoven wires
  • FIG. 5 is a sectional view of the upper portion of the shroud as shown in FIG. 4 with wires in the form of a mesh.
  • a lightweight metallic structure is made by providing a metallic wire or mesh core of a first metal and then coating it, such as by electro or vapor deposition, with a shell of a second metal to produce a composite Wire or mesh.
  • the crystal relationship and relative diffusion rates between the core metal and the shell metal is such that the core metal will diffuse preferentially into the shell metal to United States Patent 0 3,489,534 Patented Jan. 13, 1970 produce a wire or mesh having a hollow interior bounded by the shell metal. This will occur when the composite wire or mesh is heated at a temperature below the melting point of the shell metal and in the absence of a shellcrushing pressure.
  • Metals which can be used in this manner for a core material include aluminum, magnesium and their alloys.
  • Metals which can be used as the coating or shell material include iron, nickel, cobalt and their alloys.
  • the composite wire thus formed can be arranged into a mesh or other desired configuration.
  • a plurality of meshes or individual wires can be stacked beside or one upon the other or both to provide whatever thickness is desired.
  • the composite members are held in intimate contact at various points along their surfaces and heated at that temperature sufiicient to diffuse the core metal into the shell metal but below the melting point of the shell metal.
  • the result is a lightweight porous structure comprising a plurality of wires or meshes bonded one to the other, each wire or mesh having a hollow core. If more rigidity, ductility, bonding or body is desired, solid wires or powdered filler material such as brazing alloys or both can be intermixed or interwoven with the composite wires or meshes.
  • Described in co-pending application Ser. No. 606,963, filed Jan. 3, 1967 and assigned to the same assignee as this invention is a method for making hollow members which includes the making of hollow wires, meshes and tubes. It has been found that if, during heating to diffuse the core metal into the shell metal, a plurality of composite wires or meshes are maintained in contact under sufficient pressure to maintain the contat but not sufiicient to cause collapse of walls of the hollow wires produced, the wires not only can be made hollow but also can be bonded into a more rigid structure.
  • FIG. 1 the isometric sectional view of FIG. 1 shows a composite wire 10 having a core 11 most conveniently and preferably of a metal of the group aluminum, magnesium and their alloys. Surrounding the core is a coating or shell 12 of a metal into which core 11 will diffuse upon heating to a temperature such as above the melting point of core 11. Most desirable shell metals for this purpose are metals of the group of iron, cobalt, nickel and their alloys.
  • core 11 of the composite wire 10 in FIG. 1 diffuses into shell 12 to form an alloy 14 as shown in FIG. 2.
  • metal as aluminum
  • core and nickel for the shell
  • original composite Wire outside diameter d in FIG. 1 increases to hollow wire outside diameter D in FIG. 2.
  • a plurality of stacked mesh including composite wires is contained in a fixed volume during heat treatment, such increase in diameter produces a slight pressure between the wires. This assists in bonding together during processing the plurality of composite wires. Therefore, a holding or confining structure in which the plurality of wires or meshes are placed can be shaped to provide a desired arrangement.
  • FIG. 3 A sectional view of the product is shown in FIG. 4.
  • Solid wires of a nickel base alloy 24, sometimes referred to as Nichrome alloy were placed over the brazing alloy 22. In another example substantially pure nickel wire mesh was used.
  • Composite wires 26 made of 15-40 mil aluminum wire as the core with a 5-10 mil thick coating of nickel as the shell were then placed on the solid wires 24. By weight, this consisted of 2027% Al and 73-80% Ni. As shown in FIG. 5, the wires can be partially or entirely woven together into a mesh. A top holding plate 28 was placed on the stacked wire-brazing alloy combination. In order to assure bonding of the various wires and brazing alloys together and to the shroudbacking member 16, a slight holding pressure, represented by arrow 30, was applied to the stacked wires through holding .plate 28. For example, this can be accomplished by clamping strips or other clamping means well known in the art..
  • the pressure applied should be less than that which would cause collapse of the hollow wire during or after processing.
  • the clamped structure was then heated for one hour.
  • 25 mil aluminum wires were first coated with 7.5 mils of nickel by electroplating.
  • the nickel-aluminum alloy 14 in FIG, 2 was produced after diffusion of thealuminum wire into the nickel shell in an argon atmosphere furnace in which the temperature was increased over a period of about 2 hours from room temperature to 2000 F. The material was then held for /2 hour at 2000 F. after which it was slowly cooled over a period of about 1 hour. The relatively slow heat up period or rate is desirable to avoid rupture of the shell wall as a result of too rapid a diffusion and expansion.
  • a 99% aluminum core in the form of a 120 X 120 mesh of 4 mil wire in a twill weave first was coated as a unit with 1.5 mils of nickel in an electroplat-' ing bath.
  • Such coating by electroplating or vapor deposition can be accomplished readily with well known processes having suflicient throwing power to deposit nickel over virtually the entire exposed surface.
  • a substantially completely coated composits structure can be produced. Then upon heating to diffuse the core into 4 structure of the'final hollow tubular member is to be specifically avoided, then the core wires should be coated individually prior to their being woven or grouped into a mesh, fabric, metal wool and the like.
  • composite wires having a core consisting essentially of 5-35 weight percent of the composite wire are preferred for use in the present invention.
  • An improved lightweight metallic structure comprising:
  • the hollow wires being an alloy of at least one element selected from the group consisting of Al, Mg and their alloys and at least one element selected from the group consisting of Fe, Ni, Co and their alloys; the structure having a thickness of a plurality of hollow wires.
  • Animproved lightweight shroud comprising: a backing member;
  • the hollow wires being an alloy of at least one element selected from the group consisting of Al, Mg and their alloys and at least one element selected from the group consisting of Fe, Ni, Co and their alloys.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Laminated Bodies (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Wire Processing (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
US606943A 1967-01-03 1967-01-03 Lightweight metallic structure Expired - Lifetime US3489534A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US60694367A 1967-01-03 1967-01-03

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US3489534A true US3489534A (en) 1970-01-13

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US (1) US3489534A (fr)
BE (1) BE704512A (fr)
DE (1) DE1621250A1 (fr)
FR (1) FR1547594A (fr)
GB (1) GB1189698A (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3667108A (en) * 1970-04-17 1972-06-06 Us Navy Method of making a beryllium titanium composite
US3737976A (en) * 1971-04-15 1973-06-12 Whittaker Corp Method of forming filament reinforced metallic sheets
US3789498A (en) * 1971-11-01 1974-02-05 Ambac Ind Method of diffusion bonding
US3837931A (en) * 1970-03-27 1974-09-24 Hitachi Ltd Composite iron-base metal product
US3895960A (en) * 1970-08-27 1975-07-22 Westinghouse Electric Corp Diffusion-bonded battery electrode plaques
US5002838A (en) * 1988-08-23 1991-03-26 Nkk Corporation Aluminum plating substance for anodizing
US20060236887A1 (en) * 2005-02-08 2006-10-26 John Childs Delay units and methods of making the same
US20100314023A1 (en) * 2005-03-31 2010-12-16 Rene Jabado Process for Applying Material to a Component, a Fiber and a Fiber Mat
WO2013003311A1 (fr) * 2011-06-27 2013-01-03 Turbine Services Ltd. Joint de turbine brasé
US8794152B2 (en) 2010-03-09 2014-08-05 Dyno Nobel Inc. Sealer elements, detonators containing the same, and methods of making
US20180320270A1 (en) * 2017-05-08 2018-11-08 United Technologies Corporation Functionally graded environmental barrier coating
US20190047078A1 (en) * 2016-02-16 2019-02-14 Tohoku Techno Arch Co., Ltd. Method for producing nano-composite metal member and method for joining phase-separated metal solids

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2576301B1 (fr) * 1985-01-24 1992-03-13 Europ Propulsion Procede de preparation de materiaux refractaires poreux, produits nouveaux ainsi obtenus et leurs applications a la preparation d'anneaux de turbine abradables

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2271662A (en) * 1939-01-17 1942-02-03 Rubissow George Alexis Filtering element and new method for its manufacture
US3087233A (en) * 1960-11-16 1963-04-30 Fram Corp Pervious metal fiber material and method of making the same
US3123446A (en) * 1964-03-03 Porous wall construction
US3266130A (en) * 1965-10-21 1966-08-16 Fort Wayne Metals Inc Method of making a permeable airfoil skin

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3123446A (en) * 1964-03-03 Porous wall construction
US2271662A (en) * 1939-01-17 1942-02-03 Rubissow George Alexis Filtering element and new method for its manufacture
US3087233A (en) * 1960-11-16 1963-04-30 Fram Corp Pervious metal fiber material and method of making the same
US3266130A (en) * 1965-10-21 1966-08-16 Fort Wayne Metals Inc Method of making a permeable airfoil skin

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3837931A (en) * 1970-03-27 1974-09-24 Hitachi Ltd Composite iron-base metal product
US3667108A (en) * 1970-04-17 1972-06-06 Us Navy Method of making a beryllium titanium composite
US3895960A (en) * 1970-08-27 1975-07-22 Westinghouse Electric Corp Diffusion-bonded battery electrode plaques
US3737976A (en) * 1971-04-15 1973-06-12 Whittaker Corp Method of forming filament reinforced metallic sheets
US3789498A (en) * 1971-11-01 1974-02-05 Ambac Ind Method of diffusion bonding
US5002838A (en) * 1988-08-23 1991-03-26 Nkk Corporation Aluminum plating substance for anodizing
US20100064924A1 (en) * 2005-02-08 2010-03-18 John Childs Delay units and methods of making the same
US7650840B2 (en) 2005-02-08 2010-01-26 Dyno Nobel Inc. Delay units and methods of making the same
US20060236887A1 (en) * 2005-02-08 2006-10-26 John Childs Delay units and methods of making the same
US8245643B2 (en) 2005-02-08 2012-08-21 Dyno Nobel Inc. Delay units and methods of making the same
US20100314023A1 (en) * 2005-03-31 2010-12-16 Rene Jabado Process for Applying Material to a Component, a Fiber and a Fiber Mat
US8025203B2 (en) * 2005-03-31 2011-09-27 Siemens Aktiengesellschaft Process for applying material to a component, a fiber and a fiber mat
US8794152B2 (en) 2010-03-09 2014-08-05 Dyno Nobel Inc. Sealer elements, detonators containing the same, and methods of making
WO2013003311A1 (fr) * 2011-06-27 2013-01-03 Turbine Services Ltd. Joint de turbine brasé
US20190047078A1 (en) * 2016-02-16 2019-02-14 Tohoku Techno Arch Co., Ltd. Method for producing nano-composite metal member and method for joining phase-separated metal solids
US20180320270A1 (en) * 2017-05-08 2018-11-08 United Technologies Corporation Functionally graded environmental barrier coating

Also Published As

Publication number Publication date
BE704512A (fr) 1968-02-01
FR1547594A (fr) 1968-11-29
GB1189698A (en) 1970-04-29
DE1621250A1 (de) 1971-04-29

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