WO2001055471A1 - Procede de carbonitruration d'aciers a haute teneur en carbone et fortement allies - Google Patents
Procede de carbonitruration d'aciers a haute teneur en carbone et fortement allies Download PDFInfo
- Publication number
- WO2001055471A1 WO2001055471A1 PCT/EP2001/000838 EP0100838W WO0155471A1 WO 2001055471 A1 WO2001055471 A1 WO 2001055471A1 EP 0100838 W EP0100838 W EP 0100838W WO 0155471 A1 WO0155471 A1 WO 0155471A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- carbon
- carbonitriding
- nitrogen
- ammonia
- propane
- Prior art date
Links
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 44
- 238000005256 carbonitriding Methods 0.000 title claims abstract description 37
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 22
- 239000000956 alloy Substances 0.000 title claims abstract description 22
- 238000000034 method Methods 0.000 title claims abstract description 20
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 14
- 239000010959 steel Substances 0.000 title claims abstract description 14
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 71
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 49
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims abstract description 48
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 38
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 33
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 24
- 239000001294 propane Substances 0.000 claims abstract description 24
- 239000000126 substance Substances 0.000 claims abstract description 10
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 19
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 7
- 239000001569 carbon dioxide Substances 0.000 claims description 7
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 6
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 6
- 239000001257 hydrogen Substances 0.000 claims description 6
- 229910052739 hydrogen Inorganic materials 0.000 claims description 6
- 125000004435 hydrogen atom Chemical class [H]* 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 24
- 230000000694 effects Effects 0.000 description 17
- 238000006243 chemical reaction Methods 0.000 description 9
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 8
- 239000011651 chromium Substances 0.000 description 8
- 229910052804 chromium Inorganic materials 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- 238000005255 carburizing Methods 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 239000010410 layer Substances 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000002344 surface layer Substances 0.000 description 3
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 229910001566 austenite Inorganic materials 0.000 description 2
- 238000012937 correction Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- 229910000734 martensite Inorganic materials 0.000 description 2
- 238000005121 nitriding Methods 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 230000000171 quenching effect Effects 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 238000010744 Boudouard reaction Methods 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910000617 Mangalloy Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000000538 analytical sample Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 238000004227 thermal cracking Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
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
- C23C8/06—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
- C23C8/28—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 more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
Definitions
- the invention relates to a method for carbonitriding metallic workpieces by treating the workpieces in a carbonitriding atmosphere which is produced using a carbon-containing substance and ammonia
- carbonitriding uses so-called "endogas” into which ammonia is added.
- the ammonia content is in the range from 4 to 15% by volume of NH 3 .
- Methane or Propane - It is also known to produce suitable gas mixtures using an oxygen-containing organic liquid, such as methanol.
- the carburizing process is reversible when using endogas, so that there is the possibility of carburizing or decarburizing the materials.
- Atomic nitrogen is required for nitriding.
- the molecular nitrogen present in the endogas does not dissociate at the treatment temperatures sufficient in atomic nitrogen.
- ammonia is added to the embroidery, which partially decomposes into atomic nitrogen at the high treatment temperatures, which can be absorbed by the metal.
- the ammonia embroidery process is irreversible. The denitrification only takes place via the molecular nitrogen formation on the material surface:
- the carbon level of the gas phase must be set to high values. This is only possible if a carbon activity of 1 (graphite) or greater is set.
- Treatment temperatures of e.g. The levels of carbon dioxide and
- Chromium-rich alloys (chromium content> 5% by weight) and tempered steels can therefore only be carburized or carbonitrided to a limited extent in endogas.
- the invention is therefore based on the object of specifying a cost-effective method for producing a carbonitriding atmosphere for high-carbon and / or high-alloy steels, which prevents or reduces the formation of a covering layer or damage to the edge zone.
- This object is achieved in that nitrogen, ammonia and propane are used as the carbon-containing substance to generate the carbonitriding atmosphere.
- the dosage of the fresh gases nitrogen, propane and ammonia can be easily measured and adjusted, so that a predetermined, constant composition of the carbonitriding atmosphere and thus a defined and reproducible nitrogen and carburization can be achieved. Due to the comparatively low C0 2 content, the C0 2 emissions are also reduced in this process. In addition, operating costs can be saved by replacing endogas with the cheaper nitrogen.
- the process according to the invention is particularly easy to reproduce if only propane is used as the carbon-containing substance to generate the carbonitriding atmosphere.
- the water content of the carbonitriding atmosphere is preferably set to less than 0.1% by volume. This can be achieved by using a dry nitrogen / propane / ammonia mixture. As a result, the decarburizing component H 2 0 is avoided and a high carbon activity in the carbonitriding atmosphere is achieved.
- the carbon dioxide content of the carbonitriding atmosphere is less than 0.1% by volume. Because even by avoiding the decarburizing component C0 2 we achieve a high carbon activity in the carbonitriding atmosphere.
- a carbonitriding atmosphere which has between 8 and 15% by volume of hydrogen, between 5 and 8% by volume of methane and between 0.5 and 1.5% by volume of ammonia has proven to be particularly favorable for carbonitriding of high-carbon and high-alloy steels and contains a maximum of 1 vol .-% carbon monoxide.
- Methane is formed by thermal decomposition of the propane used in the invention.
- the contents of carbon dioxide and water in such a carbonitriding atmosphere are less than 0.1% by volume.
- Tests on the carbonitriding of metal components made of hardenable, chromium and manganese steel were carried out on a retort furnace. Nitrogen and propane were used to create the carbonitriding atmosphere.
- the flow rates of nitrogen, propane and ammonia were measured in each case using a flow meter and using a method which was lower than that used in the conventional method Endogas changed feed point metered.
- the sample gas for the analysis of the furnace gas atmosphere that was established was pumped out via a sampling tube.
- the reaction of the individual gas components resulted in contents of approx. 10% hydrogen, 6-7% methane, 1% residual ammonia and 0.5% carbon monoxide, so that the furnace exhaust gas burned with yellow-colored paint.
- the contents of water and carbon dioxide were below the detection limit of the measuring device (less than 0.05%) in all tests.
- the nitrogen concentration in the carburized alloy is defined by the stationary contents of hydrogen and residual ammonia in the furnace gas and by the treatment temperature. These concentrations can be measured with gas analyzers and used to calculate nitrogen activity (a N ).
- the nitrogen activity (SN) is a direct measure of the expected nitrogen concentration (CN) in the alloy.
- the correction factor ) takes into account all parameters that have a positive or negative influence on the solubility of nitrogen. It contains the alloy, gas and plant-specific influencing variables and must therefore be determined empirically.
- the carbon concentration in the carburized alloy is defined by the stationary contents of hydrogen and methane in the furnace gas and by the treatment temperature. The methane forms during the thermal cracking of the propane and through reaction of the hydrogen resulting from the ammonia dissociation with carbon.
- the carbon activity (a c ) is a direct measure of the expected carbon concentration (C c ) in the alloy.
- the correction factor takes into account all parameters that affect the solubility of carbon.
- the alloy, gas and plant-specific influencing variables are contained in the constant and must therefore also be determined empirically.
- Table 4 lists the gas concentrations measured in the furnace chamber according to the invention (data in% by volume):
- edge oxidation depth of the alloy elements such as silicon, manganese and chromium
- the use of nitrogen / popan instead of endogas is also preferable for edge oxidation reasons.
- a very low carbon monoxide content occurs in the treatment gas in the process according to the invention.
- the carbon monoxide content is between 20 vol .-% and about 23 vol .-%.
- the depletion depth of alloy elements and the resultant hem of fine-streaked periite can be reduced or avoided by the method according to the invention and the quality of the treated components can be improved.
Landscapes
- 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)
Abstract
On connaît des procédés de carbonitruration de pièces métalliques par traitement desdites pièces dans une atmosphère de carbonitruration produite à l'aide d'une part d'une substance à base de carbone et d'autre part d'ammoniac. L'invention vise, sur cette base, à mettre au point un procédé économique pour produire une atmosphère de carbonitruration pour des aciers à haute teneur en carbone et/ou fortement alliés, qui empêchent ou minimisent la formation d'une couche de couverture ou l'altération de la zone marginale. A cet effet, il est prévu pour la carbonitruration de pièces métalliques à base d'aciers à haute teneur en carbone et/ou fortement alliés, d'utiliser de l'azote, de l'ammoniac et du propane comme substance à base de carbone pour produire l'atmosphère de carbonitruration.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE10003526.4 | 2000-01-27 | ||
| DE2000103526 DE10003526A1 (de) | 2000-01-27 | 2000-01-27 | Verfahren zum Karbonitrieren von kohlenstoffreichen und hochlegierten Stählen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2001055471A1 true WO2001055471A1 (fr) | 2001-08-02 |
Family
ID=7628903
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EP2001/000838 WO2001055471A1 (fr) | 2000-01-27 | 2001-01-26 | Procede de carbonitruration d'aciers a haute teneur en carbone et fortement allies |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE10003526A1 (fr) |
| WO (1) | WO2001055471A1 (fr) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2909100A1 (fr) * | 2006-11-28 | 2008-05-30 | Snr Roulements Sa | Procede de renforcement d'une piece en acier riche en carbone par carbonitruration a basse pression. |
| WO2011098306A1 (fr) * | 2010-02-15 | 2011-08-18 | Robert Bosch Gmbh | Procédé de carbonitruration d'au moins un élément dans une chambre de traitement |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10321414B4 (de) * | 2003-05-13 | 2008-12-18 | Robert Bosch Gmbh | Verfahren zur Wärmebehandlung von metallischen Werkstücken in Kammeröfen |
| AT526716A3 (de) | 2022-12-01 | 2024-07-15 | Gottfried Poeckl | Verfahren zum Nitrieren von Bauteilen |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1156180A (en) * | 1966-01-21 | 1969-06-25 | Bohumil Prenosil | A Low Temperature Process for the Carbonitriding of Structural Steel and Cast Iron |
| US3663315A (en) * | 1969-03-26 | 1972-05-16 | Union Carbide Corp | Gas carburization and carbonitriding |
| GB1441091A (en) * | 1972-08-15 | 1976-06-30 | Barkas Werke Veb | Treatment of piston rods |
| US4035203A (en) * | 1973-12-21 | 1977-07-12 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Method for the heat-treatment of steel and for the control of said treatment |
| SU679643A1 (ru) * | 1976-02-16 | 1979-08-15 | Вологодский Политехнический Институт | Газова среда дл низкотемпературной нитроцементации |
| SU730876A1 (ru) * | 1977-06-01 | 1980-05-03 | Предприятие П/Я М-5953 | Способ химико-термической обработки изделий из быстрорежущих и инструментальных сталей |
| US4322255A (en) * | 1979-01-15 | 1982-03-30 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Heat treatment of steel and method for monitoring the treatment |
| US4461656A (en) * | 1983-03-15 | 1984-07-24 | Ross John A | Low temperature hardening of the surface of a ferrous metal workpiece in a fluidized bed furnace |
| US5626974A (en) * | 1994-08-25 | 1997-05-06 | Nsk Ltd. | Rolling bearing for use under high temperature conditions |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2524006B1 (fr) * | 1982-03-23 | 1985-10-11 | Air Liquide | Procede de durcissement superficiel de pieces metalliques |
| DE3718240C1 (de) * | 1987-05-30 | 1988-01-14 | Ewald Schwing | Verfahren zur Waermebehandlung von metallischen Werkstuecken in einer gasdurchstroemten Wirbelschicht |
-
2000
- 2000-01-27 DE DE2000103526 patent/DE10003526A1/de not_active Ceased
-
2001
- 2001-01-26 WO PCT/EP2001/000838 patent/WO2001055471A1/fr active Application Filing
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1156180A (en) * | 1966-01-21 | 1969-06-25 | Bohumil Prenosil | A Low Temperature Process for the Carbonitriding of Structural Steel and Cast Iron |
| US3663315A (en) * | 1969-03-26 | 1972-05-16 | Union Carbide Corp | Gas carburization and carbonitriding |
| GB1441091A (en) * | 1972-08-15 | 1976-06-30 | Barkas Werke Veb | Treatment of piston rods |
| US4035203A (en) * | 1973-12-21 | 1977-07-12 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Method for the heat-treatment of steel and for the control of said treatment |
| SU679643A1 (ru) * | 1976-02-16 | 1979-08-15 | Вологодский Политехнический Институт | Газова среда дл низкотемпературной нитроцементации |
| SU730876A1 (ru) * | 1977-06-01 | 1980-05-03 | Предприятие П/Я М-5953 | Способ химико-термической обработки изделий из быстрорежущих и инструментальных сталей |
| US4322255A (en) * | 1979-01-15 | 1982-03-30 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Heat treatment of steel and method for monitoring the treatment |
| US4461656A (en) * | 1983-03-15 | 1984-07-24 | Ross John A | Low temperature hardening of the surface of a ferrous metal workpiece in a fluidized bed furnace |
| US5626974A (en) * | 1994-08-25 | 1997-05-06 | Nsk Ltd. | Rolling bearing for use under high temperature conditions |
Non-Patent Citations (2)
| Title |
|---|
| DATABASE WPI Section Ch Week 198016, Derwent World Patents Index; Class M13, AN 1980-28662C, XP002166199 * |
| DATABASE WPI Section Ch Week 198051, Derwent World Patents Index; Class M13, AN 1980-91509C, XP002166200 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2909100A1 (fr) * | 2006-11-28 | 2008-05-30 | Snr Roulements Sa | Procede de renforcement d'une piece en acier riche en carbone par carbonitruration a basse pression. |
| WO2011098306A1 (fr) * | 2010-02-15 | 2011-08-18 | Robert Bosch Gmbh | Procédé de carbonitruration d'au moins un élément dans une chambre de traitement |
| US9399811B2 (en) | 2010-02-15 | 2016-07-26 | Robert Bosch Gmbh | Method for carbonitriding at least one component in a treatment chamber |
Also Published As
| Publication number | Publication date |
|---|---|
| DE10003526A1 (de) | 2001-08-09 |
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