EP0869189A1 - Process for gas quenching metallic workpieces - Google Patents
Process for gas quenching metallic workpieces Download PDFInfo
- Publication number
- EP0869189A1 EP0869189A1 EP98103643A EP98103643A EP0869189A1 EP 0869189 A1 EP0869189 A1 EP 0869189A1 EP 98103643 A EP98103643 A EP 98103643A EP 98103643 A EP98103643 A EP 98103643A EP 0869189 A1 EP0869189 A1 EP 0869189A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- gas
- quenching
- mpa
- cooling gas
- furnace
- 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.)
- Ceased
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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
- 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
- C21D1/767—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material with forced gas circulation; Reheating thereof
-
- 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
- C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
- C21D1/613—Gases; Liquefied or solidified normally gaseous material
Definitions
- the invention relates to a method for gas quenching metallic workpieces after heat treatment in a heat treatment furnace, the gas quenching is carried out either in the furnace itself or in a gas-tight chamber and wherein the cooling gas is helium, hydrogen, mixtures of helium and hydrogen or mixtures of these with an additional up to 30% inert gas for use come and the cooling gas velocity v is set so that the product from cooling gas pressure p and cooling gas velocity v a value between 10 and Assumes 240 MPa m / sec and more.
- a cooling gas pressure p in the furnace or the quenching chamber of more than 4 MPa (40 bar) is provided.
- a cooling gas pressure p im Oven or quenching chamber set above 4 MPa and up to 5.5 MPa.
- the cooling gas velocity v is set such that the product of the cooling gas pressure p and the cooling gas velocity v assumes a value between 80 and 660 MPa m / sec, preferably between 110 and 300 MPa m / sec.
- the invention is also advantageously carried out in a variant in such a way that the Fumigation of the furnace or the cooling chamber using one or more so-called nozzle blocks with flow directed directly at the workpieces.
- initially high gas flow velocities can also be used in later phases of cooling, e.g. in the second half of the cooling period, be reduced.
- Another advantageous variant of the invention is that alternatively or additionally -in addition to the usual inert gases in the field of heat treatment such as nitrogen and argon inert gases with higher energy absorption capacity such as carbon dioxide, hydrogen sulfide or water vapor is added to the low density quenching gas the 30% share of the inert gases in the quenching gas is not exceeded.
- nitrogen and argon inert gases with higher energy absorption capacity such as carbon dioxide, hydrogen sulfide or water vapor is added to the low density quenching gas the 30% share of the inert gases in the quenching gas is not exceeded.
- Carbon dioxide is particularly preferably used for this purpose.
- cooling chamber for the pressures mentioned suitably trained wall thickness and suitable closure elements for Available. This is also designed so that - in the quenching operation - essentially covering the entire cross section from top to bottom of cooling gas is flowed through. The quenched material is then placed in the cooling chamber for example ball bearing rings made of 100 Cr 6 steel, introduced as a deterrent, taking care that the workpieces are in a density and distribution are arranged so that all workpieces are caught by the cooling gas flow.
- Cooling gas flow produced, for example, in the form of a gas circuit, wherein According to the invention, this is at a pressure level of 4.5 MPa (45 bar). Furthermore, a cooling gas speed of approx. 10 m / sec is set. As a cooling gas Hydrogen gas with a temperature of 20 to 40 ° C is used acts on the workpiece batch, which is approx. 900 ° C hot. After a cooling period of approx. A workpiece temperature of less than 100 ° C is reached within 30 seconds and thus a temperature of Quench rates comparable to quench baths.
- An increase in the cooling rate is achieved here - and generally - if the cooling gas velocity is further increased, i.e. when cooling gas speeds of about 15 m / sec and more, possibly up to the range of 100 m / sec, be applied. Speeds of 20 are particularly relevant here up to 75 m / sec. This shortens the above-mentioned cooling time by a further 10 up to 15% possible. In the described way according to the present invention so particularly high requirements in connection with deterrence metallic workpieces can be fulfilled.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatments In General, Especially Conveying And Cooling (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
Description
Die Erfindung betrifft ein Verfahren zur Gasabschreckung metallischer Werkstücke nach einer Wärmebehandlung in einem Wärmebehandlungsofen, wobei die Gasabschreckung entweder im Ofen selbst oder einer gasdichten Kammer durchgeführt wird und wobei als Kühlgas Helium, Wasserstoff, Gemische aus Helium und Wasserstoff oder Gemische aus diesen mit zusätzlich bis zu 30 % Inertgas zur Anwendung kommen und dabei die Kühlgasgeschwindigkeit v so eingestellt wird, daß das Produkt aus Kühlgasdruck p und Kühlgasgeschwindigkeit v einen Wert zwischen 10 und 240 MPa m/sec und mehr animmt.The invention relates to a method for gas quenching metallic workpieces after heat treatment in a heat treatment furnace, the gas quenching is carried out either in the furnace itself or in a gas-tight chamber and wherein the cooling gas is helium, hydrogen, mixtures of helium and hydrogen or mixtures of these with an additional up to 30% inert gas for use come and the cooling gas velocity v is set so that the product from cooling gas pressure p and cooling gas velocity v a value between 10 and Assumes 240 MPa m / sec and more.
Gasabschreckverfahren, wie sie oben beschrieben sind und die mit Drücken bis zu 40 bar arbeiten, sind aus der EP 0 313 888 B1 bekannt. Diese Verfahren liefern bereits weitgehend befriedigende Abkühlgeschwindigkeiten des metallischen Behandlungsgutes, es gibt jedoch Anwendungsfälle - z.B. bei niedrig legierten Stählen - in denen eine noch weitergehende Abkühleistung wünschenswert wäre. Andererseits jedoch, erscheint die Möglichkeit, die Abkühlleistung über Druck- und/oder Gasgeschwindigkeitseinstellungen weiter zu steigern als kaum mehr möglich, da mit den vorgenannten Verfahren bereits Druckbereiche in Anwendung sind, die ohnehin schon sehr hoch liegen und die zudem, hinsichtlich der Anlagentechnik und der Motorleistung der notwendigen Gasumwälzventilatoren, anspruchsvolle Ausführungen erfordern. Dies stellt die Ausgangslage und die Aufgabenstellung vorliegender Erfindung dar.Gas quenching processes as described above and with pressures up to Working at 40 bar are known from EP 0 313 888 B1. These procedures deliver already largely satisfactory cooling rates of the metallic Goods to be treated, but there are use cases - e.g. with low alloys Steel - in which an even further cooling performance would be desirable. On the other hand, however, the possibility of cooling performance appears above To increase pressure and / or gas speed settings further than little more possible, since pressure ranges are already in use with the aforementioned methods are, which are already very high and which, in terms of Plant technology and the engine power of the necessary gas circulation fans, demanding designs. This represents the starting point and the Task of the present invention.
Der Wunsch nach weiter erhöhten Abkühlgeschwindigkeiten wird erfindungsgemäß dadurch gelöst, daß ein Kühlgasdruck p im Ofen oder der Abschreckkammer von mehr als 4 MPa (40 bar) vorgesehen wird. Vorzugsweise wird ein Kühlgasdruck p im Ofen oder der Abschreckkammer von mehr als 4 MPa und bis zu 5,5 MPa eingestellt. The desire for further increased cooling rates becomes according to the invention solved in that a cooling gas pressure p in the furnace or the quenching chamber of more than 4 MPa (40 bar) is provided. Preferably, a cooling gas pressure p im Oven or quenching chamber set above 4 MPa and up to 5.5 MPa.
Es hat sich in überraschender Weise gezeigt, daß mit der Erfindung eine weitere
Steigerung der Abkühlgeschwindigkeit im Bereich von 5 bis 20 % erzielt werden kann.
Der Erfindung steht entgegen, daß mit den vorgeschlagenen Druckbereichen in
Größenordnungen vorgedrungen wird, die bei der anlagentechnischen Realisierung in
der Regel ein aufwendigeres Vorgehen verlangen. Hierbei können jedoch Vorschläge,
wie sie die EP 0 495 151 B1 anbietet, zur Anwendung kommen, d.h. daß mindestens
Teilbereiche der Abschreckkammer oder des Ofens mit geschlossenen Zwischenvolumina
versehen werden, und diese mit einem Inertgas gespült werden. Undichtigkeiten
werden so durch Gasanalyse leicht detektierbar und Abschreckgas gelangt
nicht unmittelbar in die Umgebung. Dies ist insbesondere dann vorteilhaft, wenn als
Abschreckgas Wasserstoff verwendet wird.
Eine besonders gesteigerte Kühlleistung wird ferner dann erhalten, wenn relativ
hohe Kühlgasgeschwindigkeiten eingestellt werden. Dies ist erfindungsgemäß dann
der Fall, wenn die Kühlgasgeschwindigkeit v so eingestellt wird, daß das Produkt aus
Kühlgasdruck p und Kühlgasgeschwindigkeit v einen Wert zwischen 80 und 660
MPa m/sec, vorzugsweise zwischen 110 und 300 MPa m/sec, animmt.It has surprisingly been found that a further increase in the cooling rate in the range from 5 to 20% can be achieved with the invention. The invention stands in the way of the fact that the proposed pressure ranges advance in the order of magnitude which, as a rule, require a more complex procedure for the technical implementation of the system. Here, however, suggestions such as those offered by EP 0 495 151 B1 can be used, ie that at least partial areas of the quenching chamber or the furnace are provided with closed intermediate volumes and these are flushed with an inert gas. Leakages can be easily detected by gas analysis and quenching gas does not get directly into the environment. This is particularly advantageous if hydrogen is used as the quenching gas.
A particularly increased cooling capacity is also obtained if relatively high cooling gas speeds are set. This is the case according to the invention when the cooling gas velocity v is set such that the product of the cooling gas pressure p and the cooling gas velocity v assumes a value between 80 and 660 MPa m / sec, preferably between 110 and 300 MPa m / sec.
In allgemeinen ist in Verbindung mit vorliegender Erfindung auch darauf hinzuweisen, daß bei einem Abschreckprozeß für die erzielten Werkstoffeigenschaften entsprechend dem materialspezifischen ZTU-Schaubild die ersten Sekunden der Abkühlung entscheidend sind. Gemäß der Erfindung findet dies besondere Berücksichtigung, da eine hohe Abkühlgeschwindigkeit durch die angegebenen Maßnahmen, erhöhter Druck und Strömungsgeschwindigkeit, besonders begünstigt wird. Es ist ferner in Verbindung mit der Gasabschreckung bekannt, daß die Umwälzung von verdichteten Standardgasen wie Stickstoff und Argon in der Regel sehr hohe Ventilatorleistungen - 150 kW und mehr - erfordert und diese mit steigendem Druck weiter zunehmen. Versuche haben aber gezeigt, daß bei entsprechender Gasauswahl bzw. entsprechender Gasmixtur - wie in der Erfindung beschrieben - nur noch eine geringe Energiezufuhr pro Drucksteigerung bei gleicher Umlaufgeschwindigkeit erforderlich ist. Diese physikalische Erscheinung begünstigt das Betreiben von Abschreckeinrichtungen über 4 MPa. In general, it should also be pointed out in connection with the present invention that that in a quenching process for the material properties achieved accordingly the material-specific ZTU diagram the first few seconds of cooling are crucial. According to the invention, this is given special consideration since a high cooling rate due to the specified measures, increased Pressure and flow velocity, is particularly favored. It is also in Connection with gas quenching has been known to compress the recycle Standard gases such as nitrogen and argon generally have very high fan outputs - 150 kW and more - required and these continue to increase with increasing pressure. tries but have shown that with appropriate gas selection or corresponding Gas mixture - as described in the invention - only a small amount of energy per pressure increase at the same circulation speed is required. This physical appearance favors the operation of quenching equipment over 4 MPa.
Vorteilhaft wird die Erfindung ferner in einer Variante in der Weise ausgeführt, daß die Begasung des Ofens bzw. der Kühlkammer mittels eines oder mehrerer sog. Düsenstöcke mit direkt auf die Werkstücke gerichteter Strömung erfolgt. Die dabei ohne zusätzliche Energiezufuhr erzeugten Strömungsgeschwindigkeiten von 100 m/s und mehr führen in der so wichtigen Anfangsphase zu einer ganz besonders effektiven Abkühlung. In einer Variante können auch anfänglich hohe Gasströmgeschwindigkeiten in späteren Phasen der Abkühlung, z.B. inder zweiten Hälfte der Abkühlungszeit, reduziert werden.The invention is also advantageously carried out in a variant in such a way that the Fumigation of the furnace or the cooling chamber using one or more so-called nozzle blocks with flow directed directly at the workpieces. The one without additional energy supply generated flow velocities of 100 m / s and more lead to a particularly effective one in the very important initial phase Cooling. In one variant, initially high gas flow velocities can also be used in later phases of cooling, e.g. in the second half of the cooling period, be reduced.
Eine weitere vorteilhafte Variante der Erfindung besteht darin, daß alternativ oder zusätzlich -neben üblichen Inertgasen im Bereich der Wärmebehandlung wie Stickstoff und Argon - Inertgase mit höherer Energieaufnahmefähigkeit wie Kohlendioxid, Schwefelwasserstoff oder Wasserdampf zum Abschreckgas geringer Dichte hinzugemischt werden, wobei der 30 %-Anteil der Inertgase im Abschreckgas nicht überschritten wird. Besonders bevorzugt wird hierzu Kohlendioxid angewandt.Another advantageous variant of the invention is that alternatively or additionally -in addition to the usual inert gases in the field of heat treatment such as nitrogen and argon inert gases with higher energy absorption capacity such as carbon dioxide, hydrogen sulfide or water vapor is added to the low density quenching gas the 30% share of the inert gases in the quenching gas is not exceeded. Carbon dioxide is particularly preferably used for this purpose.
Durch die Zumischung von Inertgasen mit höherer Energieaufnahmefähigkeit wird die Abkühlgeschwindigkeit von Werkstückchargen unter Umständen weiter erhöht. Dies beruht darauf, daß die angesprochenen Gase eine höhere Wärmekapazität als z.B. Helium, Wasserstoff und auch Stickstoff besitzten, und diese somit in einem "Transportvorgang" größere Mengen an Wärme abführen können. Dem entgegen steht jedoch die Erhöhung der Dichte des Abschreckgases und damit die Erhöhung der erforderlichen Ventilatorleistung. Daher ergibt sich bei relativ niedrigen Zumischungen ein optimales Ergebnis.By adding inert gases with a higher energy absorption capacity the cooling rate of workpiece batches may increase further under certain circumstances. This is due to the fact that the gases mentioned have a higher heat capacity than e.g. Helium, hydrogen and also nitrogen, and thus in one "Transport process" can dissipate large amounts of heat. Against that However, there is the increase in the density of the quenching gas and thus the increase the required fan power. This results in relatively low admixtures an optimal result.
Anhand eines Ausführungsbeispieles wird die Erfindung nachstehend näher erläutert:The invention is explained in more detail below using an exemplary embodiment:
Es steht eine eigenständig arbeitende Kühlkammer mit für die genannten Drucke geeignet ausgebildeter Wandstärke und ebenso geeigneten Verschlußelementen zur Verfügung. Diese ist ferner so gestaltet, daß sie - im Abschreckbetrieb - im wesentlichen den gesamten Querschnitt erfassend von oben nach unten von Kühlgas durchströmt wird. In die so ausgebildete Kühlkammer wird dann das Abschreckgut, beispielsweise Kugellageringe aus einem 100 Cr 6 Stahl, zur Abschreckung eingebracht, wobei darauf zu achten ist, daß die Werkstücke in einer Dichte und Verteilung angeordnet sind, daß alle Werkstücke vom Kühlgasstrom erfaßt werden.There is an independently working cooling chamber for the pressures mentioned suitably trained wall thickness and suitable closure elements for Available. This is also designed so that - in the quenching operation - essentially covering the entire cross section from top to bottom of cooling gas is flowed through. The quenched material is then placed in the cooling chamber for example ball bearing rings made of 100 Cr 6 steel, introduced as a deterrent, taking care that the workpieces are in a density and distribution are arranged so that all workpieces are caught by the cooling gas flow.
Nach dem druckdichten Verschließen der Kühlkammer wird in dieser der beschriebene Kühlgasstrom beispielsweise in Gestalt eines Gaskreislaufs hergestellt, wobei sich dieser erfindungsgemäß auf einem Druckniveau von 4,5 MPa (45 bar) befindet. Ferner wird eine Kühlgasgeschwindigkeit von ca. 10 m/sec eingestellt. Als Kühlgas kommt Wasserstoffgas zur Anwendung, das mit einer Temperatur von 20 bis 40 ° C auf die ca. 900 °C heiße Werkstückcharge einwirkt. Nach einer Kühldauer von ca. 30 sec ist eine Werkstücktemperatur von unter 100 °C erreicht und somit eine mit Abschreckbädern vergleichbare Abschreckgeschwindigkeit.After the pressure-tight closing of the cooling chamber, the described one is described in this Cooling gas flow produced, for example, in the form of a gas circuit, wherein According to the invention, this is at a pressure level of 4.5 MPa (45 bar). Furthermore, a cooling gas speed of approx. 10 m / sec is set. As a cooling gas Hydrogen gas with a temperature of 20 to 40 ° C is used acts on the workpiece batch, which is approx. 900 ° C hot. After a cooling period of approx. A workpiece temperature of less than 100 ° C is reached within 30 seconds and thus a temperature of Quench rates comparable to quench baths.
Eine Steigerung der Abkühlgeschindigkeit wird hierbei - sowie generell - erzielt, wenn die Kühlgasgeschwindigkeit weiter erhöht wird, d.h. wenn Kühlgasgeschwindigkeiten von etwa 15 m/sec und mehr, gegebenenfalls bis in den Bereich von 100 m/sec, angewandt werden. Praktisch relevant sind hier vor allem Geschwindigkeiten von 20 bis 75 m/sec. Damit ist eine Verkürzung der obengenannten Abkühlzeit um weitere 10 bis 15 % möglich. Auf dem beschriebenen Wege gemäß vorliegender Erfindung sind also besonders hohe Anforderungen in Verbindung mit der Abschreckung metallischer Werkstücke erfüllbar.An increase in the cooling rate is achieved here - and generally - if the cooling gas velocity is further increased, i.e. when cooling gas speeds of about 15 m / sec and more, possibly up to the range of 100 m / sec, be applied. Speeds of 20 are particularly relevant here up to 75 m / sec. This shortens the above-mentioned cooling time by a further 10 up to 15% possible. In the described way according to the present invention so particularly high requirements in connection with deterrence metallic workpieces can be fulfilled.
Claims (5)
die Kühlgasgeschwindigkeit v so eingestellt wird, daß das Produkt aus Kühlgasdruck p und Kühlgasgeschwindigkeit v einen Wert von mehr als 10 MPa m/sec, vorzugsweise mehr als 40 MPa m/sec animmt, dadurch gekennzeichnet,
daß ein Kühlgasdruck p im Ofen oder der Abschreckkammer von mehr als 4 MPa (40 bar) eingestellt wird.Process for the gas quenching of metallic workpieces after heat treatment in a heat treatment furnace, the gas quenching being carried out either in the furnace itself or in a gas-tight chamber and using helium, hydrogen, mixtures of helium and hydrogen or mixtures of these with up to 30% inert gas as cooling gas Application come and do it
the cooling gas speed v is set such that the product of the cooling gas pressure p and the cooling gas speed v assumes a value of more than 10 MPa m / sec, preferably more than 40 MPa m / sec, characterized in that
that a cooling gas pressure p in the furnace or the quenching chamber of more than 4 MPa (40 bar) is set.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1997109957 DE19709957A1 (en) | 1997-03-11 | 1997-03-11 | Process for gas quenching of metallic workpieces after heat treatments |
DE19709957 | 1997-03-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0869189A1 true EP0869189A1 (en) | 1998-10-07 |
Family
ID=7822949
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP98103643A Ceased EP0869189A1 (en) | 1997-03-11 | 1998-03-02 | Process for gas quenching metallic workpieces |
Country Status (2)
Country | Link |
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EP (1) | EP0869189A1 (en) |
DE (1) | DE19709957A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19920297A1 (en) * | 1999-05-03 | 2000-11-09 | Linde Tech Gase Gmbh | Process for the heat treatment of metallic workpieces |
EP1233078A2 (en) * | 2001-02-20 | 2002-08-21 | Linde Aktiengesellschaft | Process for quenching metal workpieces |
FR2844809A1 (en) * | 2002-09-20 | 2004-03-26 | Air Liquide | Rapid cooling of metal components involves using a cooling gas mixture including a gas that absorbs infrared radiation to improve heat transfer within the component by convection and radiation |
EP2604710A1 (en) * | 2011-12-13 | 2013-06-19 | Linde Aktiengesellschaft | Method for hardening of a metallic workpiece |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102005015450B3 (en) * | 2005-04-04 | 2006-08-17 | Ipsen International Gmbh | Process to quench heat-treated metal components in an evacuated chamber by cold liquid followed by cold gas |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0313888B1 (en) * | 1987-10-28 | 1991-07-31 | ALD Vacuum Technologies GmbH | Method for the heat treatment of metallic work pieces |
EP0535319A1 (en) * | 1991-10-01 | 1993-04-07 | Ipsen Industries International Gesellschaft Mit Beschränkter Haftung | Vacuum furnace for plasma carburization of metallic workpieces |
EP0495151B1 (en) * | 1991-01-15 | 1994-06-22 | Linde Aktiengesellschaft | Method of heat treating in vacuum furnaces |
-
1997
- 1997-03-11 DE DE1997109957 patent/DE19709957A1/en not_active Withdrawn
-
1998
- 1998-03-02 EP EP98103643A patent/EP0869189A1/en not_active Ceased
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0313888B1 (en) * | 1987-10-28 | 1991-07-31 | ALD Vacuum Technologies GmbH | Method for the heat treatment of metallic work pieces |
EP0495151B1 (en) * | 1991-01-15 | 1994-06-22 | Linde Aktiengesellschaft | Method of heat treating in vacuum furnaces |
EP0535319A1 (en) * | 1991-10-01 | 1993-04-07 | Ipsen Industries International Gesellschaft Mit Beschränkter Haftung | Vacuum furnace for plasma carburization of metallic workpieces |
Non-Patent Citations (3)
Title |
---|
F. PREISSER ET AL.: "Hochdruck-Gasabschrecken .....", HTM HÄRTEREI-TECHNISCHE MITTEILUNGEN, vol. 52, no. 5, September 1997 (1997-09-01), MÜNCHEN, DE, pages 264 - 270, XP000702332 * |
VORTRAG AUF DEM 52. HÄRTEREI-KOLLOQUIUM, 9.-11. OKTOBER 1996, WIESBADEN, DE * |
W. PETER ET AL.: "Vakuum-Härteofen mit Gasabschrecksystemen", HTM HÄRTEREI-TECHNISCHE MITTEILUNGEN, vol. 51, no. 2, March 1996 (1996-03-01), MÜNCHEN, DE, pages 125 - 130, XP000588531 * |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19920297A1 (en) * | 1999-05-03 | 2000-11-09 | Linde Tech Gase Gmbh | Process for the heat treatment of metallic workpieces |
EP1233078A2 (en) * | 2001-02-20 | 2002-08-21 | Linde Aktiengesellschaft | Process for quenching metal workpieces |
EP1233078A3 (en) * | 2001-02-20 | 2003-11-26 | Linde Aktiengesellschaft | Process for quenching metal workpieces |
FR2844809A1 (en) * | 2002-09-20 | 2004-03-26 | Air Liquide | Rapid cooling of metal components involves using a cooling gas mixture including a gas that absorbs infrared radiation to improve heat transfer within the component by convection and radiation |
WO2004027098A1 (en) * | 2002-09-20 | 2004-04-01 | L'air Liquide, Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude | Rapid cooling method for parts by convective and radiative transfer |
KR100953818B1 (en) * | 2002-09-20 | 2010-04-21 | 레르 리키드 쏘시에떼 아노님 뿌르 레드 에렉스뿔라따시옹 데 프로세데 조르즈 클로드 | Method and installation for rapidly cooling metal parts using a pressurized cooling gas |
EP2604710A1 (en) * | 2011-12-13 | 2013-06-19 | Linde Aktiengesellschaft | Method for hardening of a metallic workpiece |
Also Published As
Publication number | Publication date |
---|---|
DE19709957A1 (en) | 1998-09-17 |
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