EP0662525A1 - Procédé pour empêcher l'oxydation superficielle pendant la carburation des aciers - Google Patents
Procédé pour empêcher l'oxydation superficielle pendant la carburation des aciers Download PDFInfo
- Publication number
- EP0662525A1 EP0662525A1 EP94202796A EP94202796A EP0662525A1 EP 0662525 A1 EP0662525 A1 EP 0662525A1 EP 94202796 A EP94202796 A EP 94202796A EP 94202796 A EP94202796 A EP 94202796A EP 0662525 A1 EP0662525 A1 EP 0662525A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- hydrogen
- carburizing
- gas mixture
- carbon
- nitrogen
- 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
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 34
- 239000010959 steel Substances 0.000 title claims abstract description 34
- 238000005255 carburizing Methods 0.000 title claims description 28
- 238000000034 method Methods 0.000 title claims description 16
- 238000010301 surface-oxidation reaction Methods 0.000 title 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 32
- 239000007789 gas Substances 0.000 claims abstract description 32
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 32
- 239000001301 oxygen Substances 0.000 claims abstract description 32
- 239000001257 hydrogen Substances 0.000 claims abstract description 23
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 23
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 22
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 9
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 8
- 230000000694 effects Effects 0.000 claims abstract description 7
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 claims abstract description 6
- VASIZKWUTCETSD-UHFFFAOYSA-N manganese(II) oxide Inorganic materials [Mn]=O VASIZKWUTCETSD-UHFFFAOYSA-N 0.000 claims abstract description 3
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen(.) Chemical compound [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 claims abstract 4
- 229910052799 carbon Inorganic materials 0.000 claims description 22
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 21
- 239000000203 mixture Substances 0.000 claims description 17
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims description 13
- 230000003647 oxidation Effects 0.000 claims description 11
- 238000007254 oxidation reaction Methods 0.000 claims description 11
- 229930195733 hydrocarbon Natural products 0.000 claims description 10
- 150000002430 hydrocarbons Chemical class 0.000 claims description 10
- 239000004215 Carbon black (E152) Substances 0.000 claims description 7
- 150000002431 hydrogen Chemical class 0.000 claims description 7
- 239000001294 propane Substances 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 4
- LBPGGVGNNLPHBO-UHFFFAOYSA-N [N].OC Chemical compound [N].OC LBPGGVGNNLPHBO-UHFFFAOYSA-N 0.000 claims description 3
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 3
- PPNAOCWZXJOHFK-UHFFFAOYSA-N manganese(2+);oxygen(2-) Chemical compound [O-2].[Mn+2] PPNAOCWZXJOHFK-UHFFFAOYSA-N 0.000 claims 1
- WAEMQWOKJMHJLA-UHFFFAOYSA-N Manganese(2+) Chemical compound [Mn+2] WAEMQWOKJMHJLA-UHFFFAOYSA-N 0.000 abstract description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 13
- 239000012298 atmosphere Substances 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 7
- 239000000956 alloy Substances 0.000 description 7
- 238000009792 diffusion process Methods 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000035515 penetration Effects 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 229910021398 atomic carbon Inorganic materials 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 238000005422 blasting Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000010915 one-step procedure Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000001603 reducing effect Effects 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
- C21D3/02—Extraction of non-metals
- C21D3/06—Extraction of hydrogen
-
- 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
- C23C8/06—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 gases
- C23C8/08—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 gases only one element being applied
- C23C8/20—Carburising
- C23C8/22—Carburising of ferrous surfaces
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
- C21D1/76—Adjusting the composition of the atmosphere
Definitions
- the invention relates to a method for avoiding edge oxidation when carburizing steels according to the preamble of claim 1.
- low carbon steels are annealed in carbon donors at temperatures between 800 and 950 ° C.
- the surface is enriched with carbon and hardens when quenched.
- Endogases containing approximately 20% CO, 40% H2, 40% N2 are mostly used as carbon donors.
- the base alloy elements are oxidized in the edge zone of the steels, so that they are no longer present in the subsequent microstructure formation.
- An undesirable one forms in the edge zone of the steels Structure which has unfavorable properties and requires mechanical removal or blasting of this edge zone in order to achieve the required properties of the steels (workpieces).
- Edge oxidation or internal oxidation means oxide precipitates of the above-mentioned metals within a metal grain or along the grain boundaries, which are formed by the diffused dissolved oxygen and are then dispersed in the matrix.
- the invention provides a carburizing process with only low investment and operating costs because the annealing in conventional industrial furnace systems can be carried out at atmospheric pressure.
- the edge oxidation of the steels is avoided by the heat treatment being carried out in gas phases which contain no or only little oxygen-containing molecules.
- the partial pressure of oxygen in the gas atmosphere does not exceed the formation pressure of the oxides.
- the gas components hydrogen and hydrocarbons of the gas mixture according to the invention are not oxygen-containing (oxygen-free), so that almost none Partial pressure of oxygen is present.
- the carbon transfer from the gas phase into the steel during the initial and diffusion phase is large and the required carbon content in the edge of the material (approx. 1% C) sets in relatively quickly.
- the unstable hydrocarbon (C x H y ) on the alloy surface mainly breaks down into hydrogen, methane and atomic carbon, which quickly diffuses into the material.
- the decay can take place according to the following reaction equation: C3H8 ⁇ 2 CH4 + C ad
- the resulting carbon activity in the gas phase is influenced by the amount of hydrocarbon added. Since the gas phase consists mainly of hydrogen, the C level is regulated by the methane / hydrogen ratio that arises.
- the carburization reaction via methane decay in hydrogen atmospheres is: The hydrogen content and in particular the methane content that is established are continuously analyzed and the hydrocarbon feed is regulated to a desired marginal carbon content on the basis of the actual values recorded.
- the carbon-containing gas mixture is replaced by nitrogen after carburizing and the hydrogen dissolved in the steel is thus broken down.
- the steel is kept in the nitrogen atmosphere for between 5 and 15 minutes.
- the steel 16 MnCr 5 (1% Mn; 1% Cr; 0.20% Si) was carburized in an industrial furnace system.
- the furnace system was formed with endogas at approx. 1,000 ° C before the first carburization.
- the temperature and thermal voltage of the oxygen probe or the dew point or the CO2 content were measured and registered and a clear statement was made about the quality of the furnace formation.
- the carburizing process was carried out as follows:
- the furnace gas composition was continuously analyzed for H2, CH4, CO, CO2 and H2O in both process variants throughout the entire process.
- the temperature profile was also measured and registered. Carbon and oxygen activity were continuously determined and corrected for their target values.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
- Arc Welding In General (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4400391 | 1994-01-08 | ||
| DE4400391A DE4400391A1 (de) | 1994-01-08 | 1994-01-08 | Verfahren zur Vermeidung von Randoxidation beim Aufkohlen von Stählen |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0662525A1 true EP0662525A1 (fr) | 1995-07-12 |
| EP0662525B1 EP0662525B1 (fr) | 1997-06-25 |
Family
ID=6507609
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP94202796A Expired - Lifetime EP0662525B1 (fr) | 1994-01-08 | 1994-09-27 | Procédé pour empêcher l'oxydation superficielle pendant la carburation des aciers |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5498299A (fr) |
| EP (1) | EP0662525B1 (fr) |
| AT (1) | ATE154832T1 (fr) |
| DE (2) | DE4400391A1 (fr) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2826376A1 (fr) * | 2001-06-25 | 2002-12-27 | Serthel | Procede de cementation et de carbonitruration des aciers par l'oxyde de carbone |
| FR2847591A1 (fr) * | 2002-11-25 | 2004-05-28 | Bosch Gmbh Robert | Procede de cementation de pieces en acier pour travail a chaud par carburation en depression |
| EP3168314A1 (fr) | 2015-11-13 | 2017-05-17 | Air Liquide Deutschland GmbH | Procédé de traitement thermique de pièces métalliques |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5795410A (en) * | 1997-01-23 | 1998-08-18 | Usx Corporation | Control of surface carbides in steel strip |
| US6612154B1 (en) | 1998-12-22 | 2003-09-02 | Furnace Control Corp. | Systems and methods for monitoring or controlling the ratio of hydrogen to water vapor in metal heat treating atmospheres |
| US6591215B1 (en) * | 1999-02-18 | 2003-07-08 | Furnace Control Corp. | Systems and methods for controlling the activity of carbon in heat treating atmospheres |
| DE60317703D1 (de) * | 2002-12-03 | 2008-01-03 | Moltech Invent Sa | Verfahren zur aktivierung von anoden auf basis von eisen-legierungen für aluminium-elektrogewinnungszellen |
| DE10321414B4 (de) * | 2003-05-13 | 2008-12-18 | Robert Bosch Gmbh | Verfahren zur Wärmebehandlung von metallischen Werkstücken in Kammeröfen |
| US20080149225A1 (en) * | 2006-12-26 | 2008-06-26 | Karen Anne Connery | Method for oxygen free carburization in atmospheric pressure furnaces |
| US20080149226A1 (en) * | 2006-12-26 | 2008-06-26 | Karen Anne Connery | Method of optimizing an oxygen free heat treating process |
| US20080149227A1 (en) * | 2006-12-26 | 2008-06-26 | Karen Anne Connery | Method for oxygen free carburization in atmospheric pressure furnaces |
| US20080187850A1 (en) * | 2007-02-06 | 2008-08-07 | Xerox Corporation | Tunable electrophotographic imaging member and method of making same |
| US9109277B2 (en) * | 2011-01-10 | 2015-08-18 | Air Products And Chemicals, Inc. | Method and apparatus for heat treating a metal |
| CA3024534C (fr) | 2016-05-20 | 2024-02-20 | Ideapaint, Inc. | Compositions effacables a sec et leurs procedes de realisation et d'utilisation |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1916992B2 (de) * | 1969-04-02 | 1972-06-15 | Zahnradfabnk Friedrichshafen AG, 7990 Friedrichshafen | Verfahren zur steigerung der festigkeit von einsatzgehaerteten bauteilen |
| US4152177A (en) * | 1977-02-03 | 1979-05-01 | General Motors Corporation | Method of gas carburizing |
| CH641840A5 (en) * | 1977-06-16 | 1984-03-15 | Standardgraph Filler & Fiebig | Process for increasing the abrasion resistance of workpieces of stainless steel or nickel metal alloys |
| SU1204642A1 (ru) * | 1982-04-09 | 1986-01-15 | Центральное Производственно-Техническое Предприятие По Ремонту,Наладке И Проектированию Энергетических Установок Предприятий Черной Металлургии | Способ производства тонкостенных изделий из высокоуглеродистой стали |
| US4643402A (en) * | 1985-07-24 | 1987-02-17 | Mg Industries | System for producing a regulated atmosphere for a high-temperature process |
| WO1991000367A1 (fr) * | 1989-06-30 | 1991-01-10 | Aga Ab | Traitement de cementation d'un acier avec reduction de la teneur en hydrogene dans la couche cementee |
| WO1991000929A1 (fr) * | 1989-07-07 | 1991-01-24 | Aga Ab | Procede de cementation d'elements de paliers a roulement en acier au nickel faiblement allie |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4049473A (en) * | 1976-03-11 | 1977-09-20 | Airco, Inc. | Methods for carburizing steel parts |
| US4175986A (en) * | 1978-10-19 | 1979-11-27 | Trw Inc. | Inert carrier gas heat treating control process |
| US4935073A (en) * | 1981-11-27 | 1990-06-19 | Sri International | Process for applying coatings of zirconium and/or titantuim and a less noble metal to metal substrates and for converting the zirconium and/or titanium to an oxide, nitride, carbide, boride or silicide |
| FR2586259B1 (fr) * | 1985-08-14 | 1987-10-30 | Air Liquide | Procede de cementation rapide dans un four continu |
| FR2640646B1 (fr) * | 1988-12-20 | 1993-02-05 | Air Liquide | Procede et installation de traitement thermique de cementation, carbonitruration ou chauffage avant trempe de pieces metalliques |
| US5143558A (en) * | 1991-03-11 | 1992-09-01 | Thermo Process Systems Inc. | Method of heat treating metal parts in an integrated continuous and batch furnace system |
-
1994
- 1994-01-08 DE DE4400391A patent/DE4400391A1/de not_active Withdrawn
- 1994-09-27 DE DE59403219T patent/DE59403219D1/de not_active Expired - Lifetime
- 1994-09-27 EP EP94202796A patent/EP0662525B1/fr not_active Expired - Lifetime
- 1994-09-27 AT AT94202796T patent/ATE154832T1/de not_active IP Right Cessation
- 1994-10-06 US US08/319,166 patent/US5498299A/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1916992B2 (de) * | 1969-04-02 | 1972-06-15 | Zahnradfabnk Friedrichshafen AG, 7990 Friedrichshafen | Verfahren zur steigerung der festigkeit von einsatzgehaerteten bauteilen |
| US4152177A (en) * | 1977-02-03 | 1979-05-01 | General Motors Corporation | Method of gas carburizing |
| CH641840A5 (en) * | 1977-06-16 | 1984-03-15 | Standardgraph Filler & Fiebig | Process for increasing the abrasion resistance of workpieces of stainless steel or nickel metal alloys |
| SU1204642A1 (ru) * | 1982-04-09 | 1986-01-15 | Центральное Производственно-Техническое Предприятие По Ремонту,Наладке И Проектированию Энергетических Установок Предприятий Черной Металлургии | Способ производства тонкостенных изделий из высокоуглеродистой стали |
| US4643402A (en) * | 1985-07-24 | 1987-02-17 | Mg Industries | System for producing a regulated atmosphere for a high-temperature process |
| WO1991000367A1 (fr) * | 1989-06-30 | 1991-01-10 | Aga Ab | Traitement de cementation d'un acier avec reduction de la teneur en hydrogene dans la couche cementee |
| WO1991000929A1 (fr) * | 1989-07-07 | 1991-01-24 | Aga Ab | Procede de cementation d'elements de paliers a roulement en acier au nickel faiblement allie |
Non-Patent Citations (2)
| Title |
|---|
| B. M. ESTRIN ET AL.: "Influence Of Hydrogen .....", METAL SCIENCE AND HEAT TREATMENT, vol. 28, no. 7-8, 1986, NEW YORK US, pages 542 - 547 * |
| SOVIET INVENTIONS ILLUSTRATED Section Ch Week 8634, 5 September 1986 Derwent World Patents Index; Class M13, AN 86-224202 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2826376A1 (fr) * | 2001-06-25 | 2002-12-27 | Serthel | Procede de cementation et de carbonitruration des aciers par l'oxyde de carbone |
| WO2003000947A1 (fr) * | 2001-06-25 | 2003-01-03 | Serthel | Procede de cementation et de carbonitruration des acier par l'oxyde de carbone |
| FR2847591A1 (fr) * | 2002-11-25 | 2004-05-28 | Bosch Gmbh Robert | Procede de cementation de pieces en acier pour travail a chaud par carburation en depression |
| EP3168314A1 (fr) | 2015-11-13 | 2017-05-17 | Air Liquide Deutschland GmbH | Procédé de traitement thermique de pièces métalliques |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4400391A1 (de) | 1995-07-13 |
| DE59403219D1 (de) | 1997-07-31 |
| ATE154832T1 (de) | 1997-07-15 |
| US5498299A (en) | 1996-03-12 |
| EP0662525B1 (fr) | 1997-06-25 |
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