EP0674723A1 - Substrats recouverts de nitrures metalliques - Google Patents

Substrats recouverts de nitrures metalliques

Info

Publication number
EP0674723A1
EP0674723A1 EP94904442A EP94904442A EP0674723A1 EP 0674723 A1 EP0674723 A1 EP 0674723A1 EP 94904442 A EP94904442 A EP 94904442A EP 94904442 A EP94904442 A EP 94904442A EP 0674723 A1 EP0674723 A1 EP 0674723A1
Authority
EP
European Patent Office
Prior art keywords
reaction temperature
coating
coated substrate
substrate
carbon
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.)
Withdrawn
Application number
EP94904442A
Other languages
German (de)
English (en)
Inventor
Youming Xiao
Beng Jit Tan
Steven Lawrence Suib
Francis S. Galasso
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.)
Raytheon Technologies Corp
Original Assignee
United Technologies Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by United Technologies Corp filed Critical United Technologies Corp
Publication of EP0674723A1 publication Critical patent/EP0674723A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1279—Process of deposition of the inorganic material performed under reactive atmosphere, e.g. oxidising or reducing atmospheres
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/50—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with inorganic materials
    • C04B41/5053—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with inorganic materials non-oxide ceramics
    • C04B41/5062—Borides, Nitrides or Silicides
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/1204—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material inorganic material, e.g. non-oxide and non-metallic such as sulfides, nitrides based compounds
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/1229—Composition of the substrate
    • C23C18/1245—Inorganic substrates other than metallic
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1254—Sol or sol-gel processing
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1275—Process of deposition of the inorganic material performed under inert atmosphere

Definitions

  • the present invention is directed to a method for making metal mtride coated substrates.
  • A1N aluminum nitride
  • A1N has a thermal conductivity close to that of metals and more than 10 times that of alumina (Al 2 O 3 ), a coefficient of thermal expansion comparable to silicon and silicon carbide, a high electrical resistivity, and mechanical strength comparable to alumina ceramics.
  • Metal nitride powders can be made in various ways.
  • a metal oxide powder such as Al 2 O 3 , zirconia (ZrOj), or titania (TiOz)
  • ZrOj zirconia
  • TiOz titania
  • the metal nitride powder formed by this method is, however, mixed with unreacted carbonaceous powder that detracts from the properties of the metal mtride powder.
  • the unreacted carbonaceous powder can be removed by oxidizing it at temperatures between about 600 °C and about 700 °C. At these temperatures, however, a portion of the metal nitride powder also can oxidize.
  • United States Patent 4,975,260 to Imai et al. teaches an alternate method for making a metal nitride powder by reacting a metal oxide or metal hydroxide powder with a gaseous mixture of ammonia (NH 3 ) and a hydrocarbon at a temperature ranging from 1300°C to 1600 °C. Although this method is an improvement over some prior art methods, it still leaves residual carbon in the metal nitride product. Moreover, it requires a temperature of at least 1300°C.
  • the present invention is directed to a method of making metal mtride coatings.
  • One aspect of the invention includes a method of making a metal mtride coated substrate.
  • a substrate is coated with an oxide of Al, Ti, or Zr or a hydroxide of Al, Ti, or Zr derived from a sol gel.
  • the coated substrate is heated to a reaction temperature of at least about 850 °C in a nonreactive atmosphere and contacted with a gaseous reactant mixture comprising a nitrogen source and a carbon source.
  • the molar ratio of nitrogen to carbon in the gaseous reactant mixture is at least about 15.
  • the coated substrate is maintained at the reaction temperature for a sufficient time to convert the sol gel-derived coating to a metal nitride coating.
  • Another aspect of the present invention includes a metal mtride coated substrate made by the method described above.
  • Figure 1 is a schematic of a spray coating apparatus useful with the method of the present invention.
  • Figure 2 is a schematic of a dip coating apparatus useful with the method of the present invention.
  • Figure 3 is an optical micrograph of coated SiC yarns of the present invention.
  • Figure 4 is an x-ray diffraction pattern for a A1N coating of the present invention. Best Mode for Carrying Out the Invention
  • the method of the present invention can make AIN, TiN, ZrN, or YN coatings on a variety of substrates.
  • the starting materials for the coatings include sol gel-derived coatings of an oxide or hydroxide of Al, Ti, Zr, or Y, such as Al 2 O 3 , TiO 2 , ZrO 2 , Y 2 O 3 , Al(OH) 3 , Ti(OH) 4 , Zr(OH) 4 , or Y(OH) 3 .
  • the remainder of the application describes the method of the present invention in terms of making AIN coatings from sol gel Al 2 O 3 .
  • the substrate may be any material that does not react with the AIN coating and that can withstand processing conditions.
  • the substrate may be a metal or ceramic article.
  • the substrate may be a fiber in the form of a monof ⁇ lament or a yarn. If the substrate is a yarn, the coating should be applied so it coats each fiber, rather than bridging between two or more fibers.
  • Suitable fibers include SiC monofilaments, such as BP fiber (British Petroleum, Cleveland, OH), and carbon-coated SiC yarn, such as C-Nicalon ® yarn (Nippon Carbon Co., Tokyo, Japan).
  • an Al 2 O 3 precursor coating is applied to the substrate.
  • the Al 2 O 3 precursor coating is contacted with a gaseous reactant mixture at suitable reaction conditions to form an AIN coating.
  • the gaseous reactant mixture comprises a nitrogen source and a carbon source. If NH 3 is the nitrogen source and CH 4 is the carbon source, the reaction can be written as:
  • the Al 2 O 3 coating may be any continuous, high surface area Al 2 O 3 coating, such as ⁇ -Al 2 O 3 or Al 2 O 3 made with a sol gel method.
  • the coating will be made with a sol gel method.
  • the sol gel Al 2 O 3 may be made with any method known in the art.
  • aluminum isopropoxide [AKO-Z- H ⁇ ] may be dispersed in water, for example water heated to about 75°C, in any suitable molar ratio of Al(O- ⁇ -C 3 H 7 ) 3 :H 2 O to make a sol.
  • molar ratios between about 1:100 and about 1:1000.
  • the more Al(O- -C 3 H 7 ) 3 in the sol the more viscous the sol will be.
  • the preferred ratio of AlCO-Z- H ⁇ HzO depends on the substrate to be coated.
  • Suitable A O-i- H,); may be purchased from commercial sources, including Alfa Products (Danvers, MA).
  • a small amount of HNO 3 or other acid may be added to the sol to initiate reaction.
  • the initial pH of the sol can be about 3.
  • the acidified sol may be allowed to sit until it is sufficiently viscous to make a gel than can be applied to the substrate.
  • the sol may be allowed to sit for up to 24 hr or 48 hr.
  • the sol gel-derived coating may be applied to a substrate by any conventional method.
  • the sol gel coating may be applied to a metal or ceramic article by spray coating, dip coating, spin coating, or any other suitable method.
  • Fig. 1 shows an apparatus for spraying the sol from a spraying means 2 onto the substrate 4.
  • the spraying means 2 can be any conventional spraying equipment.
  • the sol's viscosity will be controlled so it is compatible with the spraying means or other equipment used to apply the coating.
  • the sol's viscosity can be controlled by varying the amount of water in it or by adjusting its acidity.
  • the sol gel coating may be applied to the entire substrate 4 or to particular portions of the substrate. In either case, the coating will preferably cover the surfaces to which it is applied uniformly.
  • the substrate 4 can be heated, for example by placing it on a hot plate 6, before it is coated so the water in the sol evaporates rapidly. This produces a more even coating.
  • the coating may be applied to any convenient thickness and can be applied as more than one
  • Fibers and yarns are preferably coated by dipping the fibers or yarns into a sol.
  • Fig. 2 shows a dip coating apparatus in which a fiber (or yarn) 8 is dipped into a sol 10 in a suitable container 12. As the fiber 8 is withdrawn from the sol 10, a gel film 14 forms on the outside surfaces of the fiber. Preferably, the gel will be thin enough to coat each fiber in a yarn without bridging. Often, the coating on yarns will look bridged immediately after it is applied. If the sol's viscosity is properly selected, the bridging will disappear as the gel dries. Good results have been obtained with sols made with Al(O- -C 3 H 7 ) 3 :H 2 O molar ratios of about 1 : 100 to about 1 : 1000.
  • the gel on the substrate may be allowed to dry for a sufficient time to partially convert it to Al 2 O 3 and to allow it to be handled more easily.
  • the coated substrate may then be fired at a suitable temperature in a suitable atmosphere to complete the conversion of the gel to Al 2 O 3 .
  • the drying and/or firing temperature and time depend on the thickness of the coating and the particular substrate.
  • the coated substrate may be dried and/or fired at temperatures ranging from room temperature to the temperature at which the Al 2 O 3 will be converted to AIN for several minutes to several days. For example, the coated substrate may be dried at about 500°C for about 30 min. If the substrate will not react with air at the drying or firing temperature, the substrate may be dried or fired in air. If, however, the substrate will react with air, the substrate may be dried fired in an inert atmosphere. Helium is a suitable atmosphere for firing SiC fibers.
  • the coated substrate After drying and/or firing the coated substrate, it may be heated to the reaction temperature at a moderate rate, for example, about 11.5°C/min. Preferably, the rate of heating will be selected to prevent the coating from spalling off the substrate.
  • the desired reaction to AIN will occur at temperatures of at least about 850 C C.
  • Substantially complete conversion to AIN can be readily obtained at temperatures less than 1300°C, such as at temperatures of about 1000 C C and greater, although temperatures of up to about 1600°C may be used.
  • the reaction temperature therefore, may range from about 850°C to about 1600°C.
  • the reaction temperature will be less than about 1275°C or 1299°C.
  • the reaction temperature may be between about 1000°C and about 1275°C.
  • the reaction temperature will be about 1000°C to about 1100°C.
  • the reaction pressure is not critical and may be any conveniently obtainable pressure.
  • a TiO 2 or Ti(OH) 4 coating can be reacted with a gaseous reactant mixture at temperatures of at least about 750 °C. Substantially complete conversion to TiN can be obtained at temperatures greater than about 800 °C.
  • a ZrO 2 or Zr(OH) 4 coating can be reacted with a gaseous reactant mixture at temperatures of at least about 1050 °C to make
  • ZrN substantially complete conversion to ZrN can be obtained at temperatures greater than about 1100 °C. It may be desirable to make the TiN or ZrN coatings of the present invention at temperatures less than 1300°C, for example at temperatures less than 1275°C or 1299°C.
  • the coated substrate will be preheated to the reaction temperature in an inert atmosphere.
  • the substrate may be preheated in He, Ne, Ar, Kr, or Xe.
  • the inert atmosphere should be selected to avoid substrate degradation. If the coated substrate was dried or fired in an inert atmosphere, the same atmosphere may be used to heat the substrate to the reaction temperature.
  • the gaseous reactant mixture comprising nitrogen and carbon sources, is flowed into the reactor at a rate sufficient to achieve a desired N:C ratio. Reaction conditions are maintained for a sufficient time to convert the Al 2 O 3 coating to AIN. Reaction times of about 1 min to several days at reaction temperatures between about 850°C and about 1200°C have been found suitable to convert the Al 2 O 3 to AIN. Longer times may be necessary with lower temperatures. Similar reaction times are suitable to produce TiN and ZrN.
  • the gaseous reactant mixture is shut off and a nonreactive atmosphere is established in the reactor. The reactor and product are then cooled at a convenient rate.
  • the nitrogen source may be any reactive nitrogen compound that is a gas at the reaction conditions.
  • the nitrogen source may be NH 3 , N 2 H 2 , or N 2 .
  • Anhydrous NH 3 is the preferred nitrogen source because it is readily available and easy to use.
  • NH 3 may be purchased from many suppliers, including Aero All Gas Company (Hartford, CT).
  • the nitrogen source will not contain any contaminants that would produce side reactions or otherwise interfere with the nitridation reaction.
  • the carbon source should be a carbon-containing compound that is a gas at the reaction conditions.
  • the carbon source may be a hydrocarbon or an amine.
  • any hydrocarbon that is gaseous at reaction conditions may be used, alkanes having four or fewer carbon atoms are preferred because they are easier to handle.
  • amines having four or fewer carbon atoms such as methyl amine (CH 3 NH 2 ), are preferred.
  • the carbon source will be CH 4 because it is easy to obtain and work with. CH 4 may be purchased from many suppliers, including Aero All Gas Co.
  • the carbon source will not contain any contaminants that would produce side reactions or otherwise interfere with the nitridation reaction.
  • the nitrogen and carbon sources in the gaseous reactant mixture may be supplied from separate sources or from a premixed source. In either case, it is preferable that they be mixed upstream of the reactor.
  • the ratios of N:Al 2 O 3 and C:Al 2 O 3 in the reactor are not critical, although adequate amounts of gaseous reactants should be used to convert the A ⁇ O;, to AIN in a desired time.
  • the ratio of nitrogen to carbon (N:C) in the gaseous reactant mixture is critical to obtaining a substantially carbon-free product.
  • the molar ratio of N:C in the gaseous reactant mixture should be at least about 15.
  • the N:C ratio will be between about 15 and about 2000.
  • the N:C ratio will be between about 30 and about 40.
  • H 2 may be added to the gaseous reactant mixture to expand the range of conditions under which substantially carbon-free AIN can be made. Any excess of H 2 will facilitate the conversion of the sol gel-derived coating to the nitride coating. H 2 may be obtained from many commercial suppliers. The following examples demonstrate the present invention without limiting the invention's broad scope.
  • Example 1 (SiC Yam) An Al j O j sol gel was prepared by dispersing 14 g of A O-t-CjH,)., in 190 ml of H 2 O to make a sol with an Al(O- -C 3 H 7 ) 3 :H 2 O molar ratio of 1:525.
  • the sol was acidified by adding about 2 ml of concentrated HNO 3 to bring its pH to about 3 and was allowed to sit overnight to thicken. After sitting overnight, the sol's pH had rising to about 6.
  • Several C- Nicalon ® carbon coated SiC yarns (Nippon Carbon Co., Tokyo, Japan) were cut to about 3.5 cm length and taped to the bottom of a bottle. The bottle served as a convenient holder for the yarns.
  • the yarns were dipped into the sol. After 5 minutes, the yarns were slowly removed from the sol and allowed to air dry at room temperature overnight. When first removed from the sol, the gel coating the yarns looked like it bridged— hat is, coated more than one fiber in the yarns rather than each fiber. After drying, however, the gel coating was observed to coat the individual fibers without bridging.
  • the coated yarns were place in a quartz reactor and heated to 500° C in He. The temperature in the reactor was held at 500° C for 30 min to convert the gel to Al ⁇ . The reactor temperature was then raised to 1050°C at a rate of 11.5°C/min.
  • the He was turned off and NH 3 and CH 4 gases were flowed into the reactor at 400 ml/min and 30 ml/min, respectively. This created a N:C ratio of 13.33 in the reactor. After allowing the reaction to proceed for 40 min, the NH 3 and CH 4 gases were turned off and the yarns were cooled to room temperature in He.
  • An Al 2 O 3 sol gel was prepared by dispersing 2 g of Al O-t- H ⁇ in 100 ml of H 2 0 to provide an Al(O- -C 3 H 7 ) 3 :H 2 O molar ratio of 1 : 150.
  • the sol was acidified by adding about 0.5 ml of concentrated HNO 3 to bring its pH to about 3.
  • the sol was loaded into a sprayer and sprayed onto a flat, stainless steel plate to form a uniform coating about 1 ⁇ m thick.
  • the plate had been heated to about 150 °C before spraying to drive off the water in the sol as it contacted the plate.
  • the coated substrate was placed in a quartz reactor and heated to 500°C in air to convert the gel to Al 2 O 3 .
  • a He atmosphere was then established in the reactor and the reactor temperature was raised to 1050°C at a rate of 11.5°C/min. Once the reactor reached 1050°C, the He was tumed off and NH 3 and CH 4 gases were flowed into the reactor at 400 ml/min and 30 ml/min, respectively. This created a N:C ratio of 13.33 in the reactor. After allowing the reaction to proceed for 40 min, the NH 3 and CH 4 gases were tumed off and the substrate was cooled to room temperature in He.
  • X-ray photoelectron spectroscopy showed the coating was substantially carbon-free and consisted of AIN.
  • Fig. 4 is an x-ray diffraction pattern for an AIN coating on a steel substrate.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Thermal Sciences (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Dispersion Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Structural Engineering (AREA)
  • Chemical Vapour Deposition (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Inorganic Fibers (AREA)

Abstract

On peut réaliser un substrat recouvert de nitrure métallique en le recouvrant avec un oxyde d'Al, Ti ou Zr ou un hydroxyde d'Al, Ti ou Zr dérivé d'un gel de sol. On chauffe le substrat ainsi recouvert jusqu'à une température de réaction d'au moins 850 °C environ et on le met en contact avec un mélange de réactifs gazeux comprenant une source d'azote et une source de carbone. Dans ce mélange de réactifs gazeux, le rapport molaire de l'azote au carbone est d'environ 15 au minimum. On maintient ce substrat recouvert à la température de réaction suffisamment longtemps pour transformer la couche dérivée d'un gel de sol en une couche de nitrure métallique.
EP94904442A 1992-12-17 1993-12-14 Substrats recouverts de nitrures metalliques Withdrawn EP0674723A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US99192992A 1992-12-17 1992-12-17
US991929 1992-12-17
PCT/US1993/012150 WO1994013853A1 (fr) 1992-12-17 1993-12-14 Substrats recouverts de nitrures metalliques

Publications (1)

Publication Number Publication Date
EP0674723A1 true EP0674723A1 (fr) 1995-10-04

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP94904442A Withdrawn EP0674723A1 (fr) 1992-12-17 1993-12-14 Substrats recouverts de nitrures metalliques

Country Status (5)

Country Link
EP (1) EP0674723A1 (fr)
JP (1) JPH08504888A (fr)
KR (1) KR950704536A (fr)
CA (1) CA2151931A1 (fr)
WO (1) WO1994013853A1 (fr)

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KR102459619B1 (ko) 2015-09-18 2022-10-27 삼성에스디아이 주식회사 복합 음극 활물질, 이를 포함하는 리튬 전지, 및 상기 복합 음극 활물질의 제조방법
CN114436540A (zh) * 2020-11-06 2022-05-06 惠而浦欧洲中东及非洲股份公司 用于玻璃陶瓷炉灶面的耐刮擦涂层

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Publication number Priority date Publication date Assignee Title
ZA877802B (en) * 1986-11-20 1989-06-28 Minnesota Mining & Mfg Aluminum oxide/aluminum oxynitride/group ivb metal nitride abrasive particles derived from a sol-gel process
JPH01319682A (ja) * 1988-06-20 1989-12-25 Sanyo Electric Co Ltd 窒化アルミニウム膜の形成方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9413853A1 *

Also Published As

Publication number Publication date
JPH08504888A (ja) 1996-05-28
WO1994013853A1 (fr) 1994-06-23
KR950704536A (ko) 1995-11-20
CA2151931A1 (fr) 1994-06-23

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