EP0551702A1 - Procédé de nitruration d'un alliage de nickel - Google Patents

Procédé de nitruration d'un alliage de nickel Download PDF

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Publication number
EP0551702A1
EP0551702A1 EP92302169A EP92302169A EP0551702A1 EP 0551702 A1 EP0551702 A1 EP 0551702A1 EP 92302169 A EP92302169 A EP 92302169A EP 92302169 A EP92302169 A EP 92302169A EP 0551702 A1 EP0551702 A1 EP 0551702A1
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EP
European Patent Office
Prior art keywords
nickel alloy
nitriding
gas
fluorine
fluoride
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.)
Granted
Application number
EP92302169A
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German (de)
English (en)
Other versions
EP0551702B1 (fr
Inventor
Masaaki Tahara
Haruo Senbokuya
Kenzo Kitano
Tadashi Hayashida
Teruo Minato
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.)
Air Water Inc
Original Assignee
Daido Sanso Co Ltd
Daido Hoxan Inc
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Publication date
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Publication of EP0551702A1 publication Critical patent/EP0551702A1/fr
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Publication of EP0551702B1 publication Critical patent/EP0551702B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C8/00Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/34Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases more than one element being applied in more than one step
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C8/00Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/36Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases using ionised gases, e.g. ionitriding

Definitions

  • This invention relates to a method for nitriding nickel alloy for the improvement of surface hardness and other properties by forming a nitrided layer on nickel alloy surface.
  • Alloy with a high nickel content such as inconel(Ni-Cr), hastelloy(Ni-Cr-Mo) and incolloy,has been becoming widely employed because of its superior heat resistance and corrosion resistance.
  • nickel alloy such as inconel
  • the method for the improvement of surface hardness has not been established yet.
  • a method of push-out hardening for the improvement of base material intensity and a use of superplastic articles employing powder material are merely studied.
  • the method of push-out hardening increases stiffness of whole alloy, workability of the alloy is damaged.
  • superplastic articles employing powder material are difficult to put into practical use due to extremely high cost.
  • the present invention can provide a method of nitriding nickel alloy for the improvement of the surface hardness of nickel alloy by which a uniformly nitrided deep layer can be formed on the nickel alloy surface.
  • the present invention provides a method for nitriding nickel alloy which comprises steps of holding nickel alloy in a fluorine- or fluoride-containing gas atmosphere with heating and holding the fluorinated nickel alloy in a nitriding atmosphere with heating to form the surface layer of the nickel alloy into a nitrided layer.
  • the method of the invention is applied to a nickel alloy, which is nitrided in a nitriding atmosphere after having been flourided in a fluorine- or fluoride-containing gas atmosphere.
  • Nickel alloys containing more than 25 weight % nickel, for example, Ni-Cr, Ni-Cr-Mo, and Ni-Cr-Fe are mainly used in the method of the invention.
  • Nickel alloys containing not more than 25% nickel can be also used in the method of the invention. Therefore, in the invention, the term " nickel alloy" includes both alloys containing more than 25% nickel and not more than 25% nickel. However, alloy containing more than 25% nickel is more suitable. A method does not specify a shape of nickel alloy nor a level of processing. All the material, intermediate products, and finished products made of nickel alloy are included to the extent of nickel alloy in this invention.
  • Fluorine- or fluoride-containing gas for a fluorine- or fluoride-containing gas atmosphere, in which the above-mentioned nickel alloy is reacted is fluorine compound gas, such as NF3, BF3, CF4, HF, SF6, C2F6, WF6, CHF3, or SiF4. They are used independently or in combination.
  • fluorine compound gas with F in its molecule can be used as the above-mentioned fluorine- or fluoride-containing gas.
  • F2 gas formed by cracking fluorine compound gas in a heat decomposition device and preliminarily formed F2 gas are employed as the above-mentioned fluorine- or fluoride-containing gas.
  • fluorine compound gas and F2 gas are mixed for use.
  • the above-mentioned fluorine or fluoride-containing gas such as the fluorine compound gas and F2 gas can be used independently, but generally are diluted by inert gas such as N2 gas for the treatment.
  • concentration of the fluorine- or fluoride-containing gas itself in such diluted gas should amount to , for example, 10,000 to 100,000ppm, preferably 20,000 to 70,000ppm, more preferably 30,000 to 50,000ppm.
  • the above-mentioned nickel alloy is held in a heated condition in a fluorine- or fluoride-containing gas atmosphere of such concentration, and fluorided.
  • nickel alloy is held with heating at a temperature of, for example, 350 to 500°C.
  • the holding time of the above-mentioned nickel alloy in a fluorine- or fluoride-containing gas atmosphere may appropriately be selected depending on the nickel alloy species, geometry and dimension of the alloy, heating temperature and the like, generally within the range of about ten minutes to several hours. 30 minutes is a preferred exposure time.
  • the treatment of nickel alloy in such fluorine- or fluoride-containing gas atmosphere allows "N" atoms to penetrate into nickel alloy, which was impossible in the past.
  • the oxidized layer of NiO formed on the nickel alloy surface inhibits penetration of "N" atoms for nitrization.
  • the oxidized layer of NiO Upon holding nickel alloy with an oxidized layer in a fluorine- or fluoride-containing gas atmosphere with heating as mentioned above, the oxidized layer of NiO is converted to a fluorinated layer of NiF2.
  • "N" atoms for nitrization penetrate more readily into the fluorinated layer of NiF2 than into the oxidized layer of NiO, that is, a nickel alloy surface is formed which is in a suitable condition for the penetration of "N" atoms by the above-mentioned fluorination.
  • nitriding gas composing a nitriding atmosphere is a simple gas composed of NH3 only, or a mixed gas composed of NH3 and a carbon source gas, for example, RX gas. Mixture of both gases can be also used. Generally, the above-mentioned simple gas mixed with an inert gas such as N2 is used. According to the case, H2 gas is added to those gases.
  • the above-mentioned fluorinated nickel alloy is held with heating.
  • a heating condition is generally set at a temperature of 500 to 700°C, and treatment time is set within the range of 3 to 6 hours.
  • Thickness of the hardened layer basically depends on the nitriding temperature and time.
  • a sufficient fluorinated layer ordinarily can not be formed at the fluoriding temperature below 400 °C.
  • the temperature over 600°C is not appropriate for an industrial process because furnace materials in a muffle furnace are worn out due to extreme fluoriding reaction.
  • the difference between fluoriding temperature and nitriding temperature is as small as possible. For example, a proper nitriding layer is not formed by nitriding given after fluoriding and cooling once.
  • the above-mentioned fluoriding and nitriding steps are, for example, taken in a metallic muffle furnace as shown in Fig. 1, that is, the fluoriding treatment is carried out first, and then nitriding treatment is put in practice at the inside of the muffle furnace.
  • the reference numeral 1 is a muffle furnace, 2 an outer shell of the muffle furnace, 3 a heater, 4 an inner vessel, 5 a gas inlet pipe, 6 an exhaust pipe, 7 a motor, 8 a fan, 11 a metallic container, 13 a vacuum pump, 14 a noxious substance eliminator, 15 and 16 cylinders, 17 flow meters, and 18 a valve.
  • Nickel alloy articles 10 are put in the furnace 1 and fluorided by introducing fluorine- or fluoride-containing gas atmosphere such as NF3 with heating.
  • the gas is lead into the exhaust pipe 6 by the action of vacuum pump 13 and detoxicated in the noxious substance eliminator 14 before being spouted out.
  • the cylinder 15 is connected with a duct to carry out nitriding by introducing nitriding gas into the furnace 1. After nitriding, the gas is spouted out via the exhaust pipe 6 and the noxious substance eliminator 14.
  • fluoriding and nitriding treatments are put in practice.
  • a device in Fig. 2 can be employed instead of one in Fig. 1.
  • This device comprises a fluoriding chamber on the left side and a nitriding chamber on the right side.
  • the reference numeral 2' are metallic containers, 3' a heater, 5' an exhaust gas pipe, 6' and 7' open-close covers, 11' a base, 21 a furnace body with adiabatic walls, and 22 a barrier movable up and down.
  • the barrier 22 divides the inner space of the furnace body 21 into two chambers, 23 and 24.
  • the chamber 23 is designed for a fluoriding chamber and 24 is for a nitriding chamber.
  • the reference numeral 25 is a rack comprising two rails on which a metallic container 2' having nickel alloy articles therein can slide back and forth between chamber 23 and 24.
  • the reference numeral 10' is legs of the rack 25.
  • the reference numeral 26 is a gas introducing pipe which leads a fluorine- or fluoride-containing gas into the fluoriding chamber23, 27 a temperature sensor, and 28 a nitriding gas introducing pipe.
  • High-nickel based heat resistance alloy is desirable as material for the above-mentioned metallic muffle furnace 1 instead of stainless steel material.
  • This device is a continuous treatment system in which the inner temperature of a fluoriding chamber 23 is raised by the heating on nitriding in the nitriding chamber 24, nickel alloy articles are introduced into the fluoriding chamber 23 under that condition to be fluorided. After exhausting the gas in fluoriding chamber 23, the nickel alloy articles together with the metallic container are transferred to the nitriding chamber 24 by opening and shutting the barrier 22. And then, nitriding is carried out under that condition thereby conducting fluoriding and nitriding continuously.
  • NF3 is a handy gaseous substance that has no reactivity at the ordinary temperature allowing operations and detoxication of exhaust gas to be easy.
  • Ni:76, Cr:16, Fe:8 Three kinds of nickel alloy plates made of inconel 600 ( Ni:76, Cr:16, Fe:8 ), inconel 751 ( Ni:73, Cr:16, Ti:2.5 ), and hastelloy C ( Ni:56, Cr:16, Mo:7 ) were charged into a treatment furnace as shown in Fig. 1. After vacuum purging the inside of the furnace, it was heated to 550°C. Then, in that state, fluorine- or fluoride-containing gas ( NF3 10 Vo1% + N2 90 Vo1% ) was charged into the furnace to form an atmospheric pressure in it and the condition was maintained for 30 minutes.
  • fluorine- or fluoride-containing gas NF3 10 Vo1% + N2 90 Vo1%
  • nitriding gas ( NH3 50 Vo1% + N2 25 Vo1% + H2 25 Vo1% ) was introduced into the furnace and the inside of the furnace was heated to 570 °C. Nitriding treatment was carried out in this condition for 3 hours.
  • surface hardening layers B of a nitrided layer were formed on the surface of three kinds of Nickel alloy plates made of inconel 600, inconel 751, and hastelloy C respectively, and their thickness each was 15 ⁇ m, 12 ⁇ m, and 10 ⁇ m as shown in Fig. 3, Fig. 4, and Fig. 5.
  • "A" shows base material of nickel alloy.
  • Nitriding treatment was carried out in this condition for 5 hours.
  • fluoriding treatment was carried out in the same way as Example 1. Then nitriding treatment was carried out at the temperature of 620 °C for 3 hours to them while a mixed gas composed of NH3 50 Vo1% + N2 50 Vo1% was introduced into the furnaces as a nitriding gas. After nitriding them, fluoriding was carried out at the temperature of 620°C for 3 hours employing similar fluorine- or fluoride-containing gas mentioned to that of Example 1 and further nitriding treatment was carried out again at the temperature of 620°C for 3 hours employing the above-mentioned nitriding gas.
  • a mixed gas composed of F2 10 Vo1% + N2 90 Vo1% was employed as fluorine- or fluoride-containing gas. Except this difference, all the same fluoriding and nitriding treatments were carried out to three kinds of nickel alloy plates as Example 1. As a result, the same nitrided hard layers as Example 1 were formed on the surface of three kinds of plates after the treatments, and surface hardness was the same as that of Example 1.
  • the method of nitriding nickel alloy according to the invention comprises holding nickel alloy with heating in a fluorine- or fluoride-containing gas atmosphere to thereby eliminate organic and inorganic contaminants stuck to nickel alloy and at the same time causing an oxidised layer on the nickel alloy surface to be converted to a fluorinated layer, and then subjecting the alloy to the nitriding treatment. Since the oxidised layer on the nickel alloy surface is converted to a fluorinated layer in that manner, an existence of the fluorinated layer protects the nickel alloy surface. Therefore, even after a lapse of certain time from fluoriding to nitriding, the above-mentioned fluorinated layer protects the nickel alloy surface.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
EP92302169A 1992-01-14 1992-03-13 Procédé de nitruration d'un alliage de nickel Expired - Lifetime EP0551702B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP4024763A JP2501062B2 (ja) 1992-01-14 1992-01-14 ニッケル合金の窒化方法
JP24763/92 1992-01-14

Publications (2)

Publication Number Publication Date
EP0551702A1 true EP0551702A1 (fr) 1993-07-21
EP0551702B1 EP0551702B1 (fr) 1998-06-10

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EP92302169A Expired - Lifetime EP0551702B1 (fr) 1992-01-14 1992-03-13 Procédé de nitruration d'un alliage de nickel

Country Status (6)

Country Link
EP (1) EP0551702B1 (fr)
JP (1) JP2501062B2 (fr)
KR (1) KR100247657B1 (fr)
CN (1) CN1032264C (fr)
DE (1) DE69225880T2 (fr)
TW (1) TW198070B (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0569637A1 (fr) * 1992-05-13 1993-11-18 Daido Hoxan Inc. Produits en alliage de nickel
EP0659920A1 (fr) * 1993-12-07 1995-06-28 Daido Hoxan Inc. Dent de peigne de métier à tisser durcie en surface
EP0707104A3 (fr) * 1994-08-24 1997-10-08 Dornier Gmbh Lindauer Procédé d'augmentation de la résistance des dents de peigne de tissage
US6461448B1 (en) 1998-08-12 2002-10-08 Swagelok Company Low temperature case hardening processes
US6547888B1 (en) 2000-01-28 2003-04-15 Swagelok Company Modified low temperature case hardening processes
CN103074574A (zh) * 2012-12-14 2013-05-01 四川大学 一种Ni基合金工件低温盐浴氮化工艺
CN105944746B (zh) * 2016-05-18 2018-09-14 中国科学院理化技术研究所 一种碳负载氮化镍催化剂及其制备方法和应用

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2881111B2 (ja) * 1994-06-17 1999-04-12 大同ほくさん株式会社 鋼の窒化方法
SE511082C2 (sv) * 1996-12-20 1999-08-02 Btg Eclepens Sa Beläggningsblad
US6165597A (en) * 1998-08-12 2000-12-26 Swagelok Company Selective case hardening processes at low temperature
JP4947932B2 (ja) * 2005-07-26 2012-06-06 エア・ウォーターNv株式会社 金属のガス窒化方法
JP4881049B2 (ja) * 2006-04-11 2012-02-22 新日本製鐵株式会社 電気メッキ用コンダクターロール
JP2009197254A (ja) * 2008-02-19 2009-09-03 Osaka Industrial Promotion Organization Ni基2重複相金属間化合物合金の表面処理方法,および,表面処理したNi基2重複相金属間化合物合金
JP2010070844A (ja) * 2009-02-24 2010-04-02 Air Water Inc 熱処理炉の使用方法および熱処理方法ならびに熱処理炉
US8377234B2 (en) 2010-04-26 2013-02-19 King Fahd University Of Petroleum And Minerals Method of nitriding nickel-chromium-based superalloys
CN102330062B (zh) * 2011-10-18 2013-01-02 沈阳大学 一种氮化钛/镍纳米多层薄膜的制备方法
CN102943231B (zh) * 2012-10-30 2015-07-08 江苏大学 铝及铝合金表面三段气体氮化方法
DE102013218303A1 (de) * 2013-09-12 2015-03-12 Bosch Mahle Turbo Systems Gmbh & Co. Kg Abgasturbolader mit Turbine
CN106884134B (zh) * 2015-12-16 2020-07-03 中国科学院上海应用物理研究所 一种镍基合金的表面钝化处理方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3129124A (en) * 1959-12-30 1964-04-14 Gen Electric Process for producing interlaminar insulation for electrical apparatus
EP0352061A2 (fr) * 1988-07-20 1990-01-24 Hashimoto Chemical Industries Co., Ltd. Matériau métallique avec film passivé par fluoration et appareil constitué par ce matériau
EP0408168A1 (fr) * 1989-07-10 1991-01-16 Daidousanso Co., Ltd. Procédé pour le prétraitement préalable de matériaux métalliques et procédé pour la nitruration d'acier

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3129124A (en) * 1959-12-30 1964-04-14 Gen Electric Process for producing interlaminar insulation for electrical apparatus
EP0352061A2 (fr) * 1988-07-20 1990-01-24 Hashimoto Chemical Industries Co., Ltd. Matériau métallique avec film passivé par fluoration et appareil constitué par ce matériau
EP0408168A1 (fr) * 1989-07-10 1991-01-16 Daidousanso Co., Ltd. Procédé pour le prétraitement préalable de matériaux métalliques et procédé pour la nitruration d'acier

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 8, no. 98 (C-221)(1535) 9 May 1984 & JP-A-59 13 065 ( FUJITSU ) 23 January 1984 *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0569637A1 (fr) * 1992-05-13 1993-11-18 Daido Hoxan Inc. Produits en alliage de nickel
EP0659920A1 (fr) * 1993-12-07 1995-06-28 Daido Hoxan Inc. Dent de peigne de métier à tisser durcie en surface
US5447181A (en) * 1993-12-07 1995-09-05 Daido Hoxan Inc. Loom guide bar blade with its surface nitrided for hardening
EP0707104A3 (fr) * 1994-08-24 1997-10-08 Dornier Gmbh Lindauer Procédé d'augmentation de la résistance des dents de peigne de tissage
US6461448B1 (en) 1998-08-12 2002-10-08 Swagelok Company Low temperature case hardening processes
US6547888B1 (en) 2000-01-28 2003-04-15 Swagelok Company Modified low temperature case hardening processes
CN103074574A (zh) * 2012-12-14 2013-05-01 四川大学 一种Ni基合金工件低温盐浴氮化工艺
CN105944746B (zh) * 2016-05-18 2018-09-14 中国科学院理化技术研究所 一种碳负载氮化镍催化剂及其制备方法和应用

Also Published As

Publication number Publication date
JPH05195193A (ja) 1993-08-03
CN1032264C (zh) 1996-07-10
DE69225880D1 (de) 1998-07-16
TW198070B (fr) 1993-01-11
DE69225880T2 (de) 1998-12-17
EP0551702B1 (fr) 1998-06-10
JP2501062B2 (ja) 1996-05-29
CN1074489A (zh) 1993-07-21
KR930016559A (ko) 1993-08-26
KR100247657B1 (ko) 2000-04-01

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