EP0175157B1 - Verfahren zum Borieren von Metallen und Metall-Legierungen mittels fester Boriermittel - Google Patents

Verfahren zum Borieren von Metallen und Metall-Legierungen mittels fester Boriermittel Download PDF

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Publication number
EP0175157B1
EP0175157B1 EP85110451A EP85110451A EP0175157B1 EP 0175157 B1 EP0175157 B1 EP 0175157B1 EP 85110451 A EP85110451 A EP 85110451A EP 85110451 A EP85110451 A EP 85110451A EP 0175157 B1 EP0175157 B1 EP 0175157B1
Authority
EP
European Patent Office
Prior art keywords
boriding
fluidized bed
metal
boron
borating
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
Application number
EP85110451A
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German (de)
English (en)
French (fr)
Other versions
EP0175157A3 (en
EP0175157A2 (de
Inventor
Alfred Graf Dipl.-Ing. Von Matuschka (Fh)
Norbert Trausner
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.)
Elektroschmelzwerk Kempten GmbH
Original Assignee
Elektroschmelzwerk Kempten GmbH
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Filing date
Publication date
Application filed by Elektroschmelzwerk Kempten GmbH filed Critical Elektroschmelzwerk Kempten GmbH
Priority to AT85110451T priority Critical patent/ATE42577T1/de
Publication of EP0175157A2 publication Critical patent/EP0175157A2/de
Publication of EP0175157A3 publication Critical patent/EP0175157A3/de
Application granted granted Critical
Publication of EP0175157B1 publication Critical patent/EP0175157B1/de
Expired 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
    • C23C8/00—Solid 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
    • C23C8/60—Solid 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 solids, e.g. powders, pastes
    • C23C8/62—Solid 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 solids, e.g. powders, pastes only one element being applied
    • C23C8/68—Boronising
    • C23C8/70—Boronising of ferrous surfaces
    • 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
    • C23C8/00—Solid 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
    • C23C8/60—Solid 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 solids, e.g. powders, pastes
    • C23C8/62—Solid 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 solids, e.g. powders, pastes only one element being applied
    • C23C8/68—Boronising

Definitions

  • the parts to be borated are arranged in containers and tightly surrounded with boron-releasing powder.
  • the containers are then placed in a preheated oven and kept at temperatures around 800 ° C to 1100 ° C, then cooled and then emptied.
  • the borating agent usually contains crystalline or amorphous boron, boron carbide, ferroboron, borax or mixtures of at least two of these components as a boron-releasing substance, for example carbon black as fillers.
  • the temperature treatment is carried out in chamber, pot, belt conveyor, chain conveyor or vacuum ovens.
  • This patent therefore teaches the teaching of a metal coating process in a fluidized bed, in which solid and gaseous reactants react to form volatile compounds, which then decompose in the specified temperature range when they come into contact with the metal surfaces to be coated, forming a metal coating thereon, this thermal decomposition reaction being caused by Application of negative pressure is favored.
  • Suggestions for a boronization process in a fluidized bed, in which a boride diffusion layer is to be generated by exclusively solid reaction participants in a thermochemical reaction on the metal surfaces to be borated from iron and non-ferrous metals could not be derived from this prior art.
  • the activators required to trigger this thermochemical reaction in the temperature range customary for boronization processes cannot be introduced into the reaction space as gaseous reactants, but must be available as solids in close contact with the boron-releasing solids.
  • the object of the invention is therefore to provide a method for producing a solid borating agent To develop a granular form which enables a metal to be easily and quickly borated in a fluidized bed with fluidizing gas which is not involved in the chemical reaction.
  • the shape and size of the particles alone are not decisive, but rather the combination of the components required for boronizing (boron donors, activators, fillers) in one and the same particle. This is to ensure that the essential components hit the surface to be borated at the same time, but also that premature disintegration of the granules under the hard fluidized bed conditions is avoided.
  • boron granules which consists of almost spherical particles with a particle size of 0.025 mm to 5.0 mm based on boron-releasing substances, activators, fillers and binders, the boron granules by spray drying an aqueous suspension from the constituents mentioned using emulsifiers, auxiliaries and binders, selected from mono-, di- and / or polysaccharides, at temperatures between 120 ° C to 750 ° C.
  • the boron granules produced by this process are preferably used for boronizing metals and metal alloys in a fluidized bed at a temperature of 580 ° C. to 1300 ° C., the fluidized bed being generated with fluidizing gas which is not involved in the chemical reaction.
  • a borating agent in granular form is known from DE-A-2 127 096 (H. Krzyminski, Manual Gold- und Silber-Scheideweg 14, 1972).
  • the known boron powders cannot be used in this process because of their grain size and grain distribution.
  • all solid formulations of borating agents produced according to the invention can be used for boronizing in the fluidized bed, the almost spherical grain of which can be kept in a fluidized state at the reaction temperature in the flowing gaseous medium. Almost spherical particles with a grain size of 0.05 to 2.0 mm are preferred.
  • the boron granules produced according to the invention can be formulated, for example, from all powders which have hitherto been successfully used for boronizing metals.
  • boron-releasing substances they can contain amorphous or crystalline boron, boron carbide, borax or metal borides, or mixtures of at least two of these substances.
  • Boron carbide is particularly preferred. Soot, silicon carbide, aluminum, magnesium and silicon oxides, silicates, non-boronable metals, their mixtures or similar substances can serve as fillers which are also extenders.
  • the borating agents can contain all substances, individually or in a mixture, which were previously used as activators in the boriding of metals and their alloys. Complex fluorides, in particular potassium tetrafluoroborate, are preferred.
  • a method that is not typical for this purpose is used to granulate the borating agent: spray drying.
  • This process is generally used to make highly disperse and redispersible particles, i.e. H. Particles of low mechanical stability are used.
  • the spray drying of the boron mixture forms particles which are mechanically stable and, owing to their almost spherical geometry, their particle size, their narrow particle size distribution and their dimensional stability, are particularly suitable for use in a fluidized bed process under reaction conditions.
  • binders, a dispersing agent which is inert towards the powder constituents and emulsifiers are added to the powder to be granulated.
  • Saccharides, disaccharides, polysaccharides and mixtures of at least two of these substances are preferred as binders.
  • Water is preferred as the dispersing agent which is inert towards the powder components for environmental and cost reasons.
  • 10 to 100 percent by weight, preferably 20 to 70 percent by weight, of dispersing agent are added. It is possible to use more dispersants, but it requires higher energy consumption or lower throughput when spray drying.
  • Emulsifiers can be added to the mixture to be granulated.
  • auxiliary substances such as protective colloids, anti-foaming agents and spraying aids can be added.
  • Binder is preferably used in amounts of 2 to 30 percent by weight, based on the sum of the weight of dry granules, i.e. H. boron-releasing substance, fillers and activators, emulsifiers, auxiliaries and binders used; Amounts between 5 and 20 percent by weight are particularly preferred.
  • the amounts of boron-imparting substance can be between 2 and 90 percent by weight, based on the dry granulate, depending on the affinities of the surfaces to be borated.
  • the activator is used in amounts of 1 to 15, preferably 3 to 8 percent by weight. Larger amounts of activator have no advantages.
  • the boriding granulate can be used as the only bulk material, but it can also be used in a mixture with a granulate which is inert to the boron-releasing substance.
  • Such inert granules can consist, for example, of the fillers mentioned above.
  • the fluidized bed boriding process is carried out in a retort made of a gas-tight material which is stable at the reaction temperature, preferably in ceramic or ceramic-coated retorts.
  • Inert gases and gas mixtures or reducing gases are preferably used as fluidizing gases and gas mixtures used.
  • inert gases or gas mixtures are nitrogen, argon and their mixtures.
  • reducing gases or gas mixtures are hydrogen, ammonia cracking gas, forming gas (5-30% hydrogen, 70-95% nitrogen), hydrocarbons, mixtures of at least two of these reducing gases and mixtures of at least one reducing gas with at least one inert gas.
  • the boriding process is carried out at temperatures from 580 ° C. to 1300 ° C., preferably at 580 ° C. to 1100 ° C., in particular at 800 ° C. to 1100 ° C.
  • the fluidized bed boring process allows a continuous or semi-continuous procedure for boring individual and serial parts, also in connection with subsequent treatments. In general, it is advisable to preheat the workpieces to be borated before the actual boriding step. Borier granules that have largely been used up can be removed from the fluidized bed during the process, for example by suction or pneumatic conveying; Unused borating agent can be added to the reactor at any time. Fully continuous operation can be achieved, for example, by guiding the boric agent stream in the moving bed.
  • the boriding process can be followed by other process steps that have proven themselves in metal treatment. Boronizing steels can be followed, for example, by diffusion annealing, austenitizing, quenching and / or tempering.
  • the fluidized bed process allows a more economical use of the relatively expensive boriding medium.
  • the fluidized bed boron creates a closed boride layer of uniform thickness.
  • the fluidized bed process can borate all metals and metal alloys that could also be borated in the previously known processes. Examples of these metals or metal alloys are iron, cobalt, nickel, titanium, steels, hard metal and alloys which contain iron, cobalt, nickel and / or titanium.
  • a single-phase iron boride layer is achieved on the surface of iron-containing alloys or iron, ie the iron boride formed consists essentially of Fe 2 B.
  • Most other processes produce two-phase layers, one phase of which contains Fe 2 B and the other of which FeB. Tensions can occur in such two-phase layers containing iron boride, which ultimately lead to cracks.
  • a plate made of Ck 45 steel was suspended in a boriding agent prepared according to A in a fluidized bed at 920 ° C. and kept at this temperature for 2 hours. After this time . cooled the sample in the raised shaft of the fluidized bed furnace in the gas atmosphere. Forming gas (95% nitrogen, 5% hydrogen) was used as the fluidizing gas. The surface of the sample was free of borating agent. Under these boriding conditions, a single-phase boride layer with a thickness of approx. 100 ⁇ m was created.
  • Pawls and switch cams made of St 37 K steel were borated according to Example 1, but for 3 hours, at 920 ° C. in a fluidized bed. Forming gas (90% nitrogen, 10% hydrogen) was used as the fluidizing gas.
  • the cut examination showed a single-phase boride layer thickness of approx. 140 IL m.
  • the gears were removed from the fluidized bed and then quenched in an oil bath.
  • the gears had a single-phase boride layer 30 wm thick.
  • the duration of the treatment from preparation to the end of curing was approximately 2 hours. According to the previously known methods, a treatment cycle of at least two days was necessary to achieve an equivalent result.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
  • Catalysts (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Powder Metallurgy (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Adhesives Or Adhesive Processes (AREA)
EP85110451A 1984-08-23 1985-08-20 Verfahren zum Borieren von Metallen und Metall-Legierungen mittels fester Boriermittel Expired EP0175157B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85110451T ATE42577T1 (de) 1984-08-23 1985-08-20 Verfahren zum borieren von metallen und metalllegierungen mittels fester boriermittel.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843431044 DE3431044A1 (de) 1984-08-23 1984-08-23 Verfahren zum borieren von metall und metall-legierungen mittels fester boriermittel
DE3431044 1984-08-23

Publications (3)

Publication Number Publication Date
EP0175157A2 EP0175157A2 (de) 1986-03-26
EP0175157A3 EP0175157A3 (en) 1986-04-02
EP0175157B1 true EP0175157B1 (de) 1989-04-26

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Family Applications (1)

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EP85110451A Expired EP0175157B1 (de) 1984-08-23 1985-08-20 Verfahren zum Borieren von Metallen und Metall-Legierungen mittels fester Boriermittel

Country Status (6)

Country Link
US (1) US4637837A (enrdf_load_stackoverflow)
EP (1) EP0175157B1 (enrdf_load_stackoverflow)
JP (1) JPS6160876A (enrdf_load_stackoverflow)
AT (1) ATE42577T1 (enrdf_load_stackoverflow)
CA (1) CA1230804A (enrdf_load_stackoverflow)
DE (2) DE3431044A1 (enrdf_load_stackoverflow)

Families Citing this family (33)

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DE3622668C1 (en) * 1986-07-05 1988-02-11 Ewald Schwing Fluidised bed kiln for the heat treatment of metallic objects
JPH0819514B2 (ja) * 1986-07-07 1996-02-28 株式会社豊田中央研究所 表面処理方法およびその装置
DE3630487A1 (de) * 1986-09-08 1988-03-10 Kempten Elektroschmelz Gmbh Verfahren zum randschichthaerten von werkstuecken und vorrichtung zur durchfuehrung des verfahrens
US5242741A (en) * 1989-09-08 1993-09-07 Taiho Kogyo Co., Ltd. Boronized sliding material and method for producing the same
US5303904A (en) * 1990-01-18 1994-04-19 Fike Corporation Method and apparatus for controlling heat transfer between a container and workpieces
US5407498A (en) * 1990-01-18 1995-04-18 Kemp Development Corporation Mechanically fluidized retort and method for treating particles therein
US5324009A (en) * 1990-01-18 1994-06-28 Willard E. Kemp Apparatus for surface hardening of refractory metal workpieces
US5316594A (en) * 1990-01-18 1994-05-31 Fike Corporation Process for surface hardening of refractory metal workpieces
US5595601A (en) * 1990-09-14 1997-01-21 Valmet Corporation Coating bar for a bar coater
US5264247A (en) * 1990-09-14 1993-11-23 Valmet Paper Machinery Inc. Process for the manufacture of a coating bar for a bar coater
JP3189507B2 (ja) * 1992-06-30 2001-07-16 株式会社豊田中央研究所 表面処理装置
RU2149917C1 (ru) * 1995-09-21 2000-05-27 Уральский государственный технический университет Способ бороникелирования стальных изделий в псевдоожиженном слое
RU2135631C1 (ru) * 1997-12-02 1999-08-27 Новочеркасский государственный технический университет Способ борирования поверхности стали для эмалирования
DE19830654C2 (de) * 1998-07-09 2002-06-27 Durferrit Gmbh Boriermittel, seine Verwendung und Verfahren zur Erzeugung einphasiger, Fe¶2¶B-haltiger Boridschichten
RU2132403C1 (ru) * 1998-09-01 1999-06-27 Акционерное общество "Тульский проектно-конструкторский технологический институт машиностроения" Способ химико-термической обработки
US6478887B1 (en) * 1998-12-16 2002-11-12 Smith International, Inc. Boronized wear-resistant materials and methods thereof
KR100326093B1 (ko) * 1999-07-02 2002-03-07 김점동 보로나이징 분말 및 이를 이용하여 금속표면에 보라이드층을형성하는 방법
US6601315B2 (en) 2000-12-14 2003-08-05 Bausch & Lomb Incorporated Combined fluidized bed dryer and absorption bed
EP1587676A4 (en) * 2002-11-15 2010-07-21 Univ Utah Res Found TITANIUM BORIDE INTEGRAL COATINGS ON TITANIUM SURFACES AND CORRESPONDING METHODS
US20060074491A1 (en) * 2004-09-30 2006-04-06 Depuy Products, Inc. Boronized medical implants and process for producing the same
US7325973B2 (en) * 2005-04-13 2008-02-05 Smith Thomas J Systems and methods for reducing slide bearing tolerances
US7459105B2 (en) * 2005-05-10 2008-12-02 University Of Utah Research Foundation Nanostructured titanium monoboride monolithic material and associated methods
WO2007038192A2 (en) * 2005-09-22 2007-04-05 Skaffco Engineering & Manufacturing, Inc. Plasma boriding method
US20070078521A1 (en) * 2005-09-30 2007-04-05 Depuy Products, Inc. Aluminum oxide coated implants and components
US20080029305A1 (en) * 2006-04-20 2008-02-07 Skaff Corporation Of America, Inc. Mechanical parts having increased wear resistance
CA2680858A1 (en) * 2007-03-22 2008-09-25 Skaff Corporation Of America, Inc. Mechanical parts having increased wear-resistance
US8419934B1 (en) 2008-10-30 2013-04-16 Sundance Spas, Inc. Filter
US20100176339A1 (en) * 2009-01-12 2010-07-15 Chandran K S Ravi Jewelry having titanium boride compounds and methods of making the same
US8894770B2 (en) 2012-03-14 2014-11-25 Andritz Iggesund Tools Inc. Process and apparatus to treat metal surfaces
US20170320171A1 (en) * 2016-05-06 2017-11-09 Siemens Energy, Inc. Palliative superalloy welding process
WO2018169834A1 (en) 2017-03-14 2018-09-20 Bwt Llc Method for using boronizing reaction gases as a protective atmosphere during boronizing, and reaction gas neutralizing treatment
WO2018169827A1 (en) 2017-03-14 2018-09-20 Bwt Llc Boronizing powder compositions for improved boride layer quality in oil country tubular goods and other metal articles
US11066308B2 (en) * 2019-02-05 2021-07-20 United Technologies Corporation Preparation of metal diboride and boron-doped powders

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DE2127096C3 (de) * 1971-06-01 1980-11-06 Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler, 6000 Frankfurt Verfahren zum Borieren von Metallen, insbesondere von Stahl und Eisen
JPS5073841A (enrdf_load_stackoverflow) * 1973-11-01 1975-06-18

Also Published As

Publication number Publication date
DE3431044A1 (de) 1986-03-06
US4637837A (en) 1987-01-20
CA1230804A (en) 1987-12-29
ATE42577T1 (de) 1989-05-15
DE3569754D1 (en) 1989-06-01
JPH041064B2 (enrdf_load_stackoverflow) 1992-01-09
EP0175157A3 (en) 1986-04-02
JPS6160876A (ja) 1986-03-28
EP0175157A2 (de) 1986-03-26

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