US3730863A - Method of treating workpieces in a glow discharge - Google Patents

Method of treating workpieces in a glow discharge Download PDF

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Publication number
US3730863A
US3730863A US00114162A US3730863DA US3730863A US 3730863 A US3730863 A US 3730863A US 00114162 A US00114162 A US 00114162A US 3730863D A US3730863D A US 3730863DA US 3730863 A US3730863 A US 3730863A
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container
electrode
workpiece
glow discharge
workpieces
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US00114162A
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English (en)
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K Keller
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32018—Glow discharge
    • 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
    • C23C8/36—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 using ionised gases, e.g. ionitriding
    • 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
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G5/00—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32431—Constructional details of the reactor
    • H01J37/32697—Electrostatic control

Definitions

  • the present invention relates to a method of treating workpieces, particularly of iron and steel, in a metal container in a gas atmosphere by means of a glow discharge.
  • the workpieces at least temporarily form the cathode and the metal container the anode.
  • a supplementary metallic electrode which shields the workpieces against the container is provided.
  • This invention further relates to a device for the performance of the said method.
  • a number of processes for the treatment of workpieces in a glow discharge in a gas atmosphere are know, by way of example for nitriding workpieces made or iron and steel in a nitrogenous gas atmosphere.
  • the workpieces normally assume a temperature, by way of example Within the range from 450 to 550 C.
  • a glow discharge was ignited with a relatively low voltage while strongly reducing discharge energy and taking appropriate measures to prevent the glow discharge from changing into an arc so that the traces of burning and melting caused by the area of impact of such an arc could be avoided.
  • the starting process must be continued with rising energy until all imperfections present on the surface of the workpieces, such as traces of grease and dirt, gas inclusions, shrink holes and the like, are eliminated and the workpiece has reached the temperature required for the performance of the desired treatment. It is only after this first period that the treatment with the full energy of discharge commonly 3,730,863 Patented May 1, 1973 begins through a second period, the treatment process proper.
  • the present invention has for its object the simplification of the performance of such processes and relates to a method of treating workpieces, particularly made of iron and steel, in a metal container in a gas atmosphere by means of a glow discharge, in which the workpieces form the cathode and the metal container the anode at least temporarily and in which an additional metallic electrode is arranged which shields the workpieces from the container.
  • the method is characterized in that this additional electrode is operated, during a first space of time, with a lower potential than the container and that a glow discharge is maintained between it and the workpiece until the imperfections of the surfaces of the workpieces have been removed whereupon, during a second space of time, the electrode is electrically connected to the container and the glow discharge maintained between it and the workpieces is run with the greater energy required.
  • This invention further relates to a device for the performance of this method using a container made of metal in which the workpieces to be treated are insulatedly arranged and connected to a pole of a voltage source which is at least temporarily negative, via an insulated current lead-in, the other pole of the said voltage source being connected to the container.
  • the device is characterized by an additional metallic electrode located between the workpieces and the container wall which shields the workpieces, the said electrode being insulated in respect of the container and connected, via an insulated current lead-in, with a switching device located outside the container.
  • FIG. 1 is a longitudinal section of an embodiment of a device according to this invention.
  • FIG. 2 is a further embodiment of a device
  • FIG. 3 is a diagrammatic plan view of the electrode 10 in FIG. 2, and
  • FIG. 4 is a diagrammatic elevation of a further embodiment of the electrode 10 in FIG. 2.
  • the device according to FIG. 7 comprises a metallic container 1 preferably made of iron, shown in a diagrammatic longitudinal section, and closed by a metallic cover 2 and a base plate 3.
  • a suction connection 4 communicating with the interior of the container is a pump unit which maintains a predetermined underpressure, by way of example inferior to 10 mm. Hg, while a gas supply connection 5 delivers the gas mixture desired for the con templated treatment to the container.
  • a gas supply connection 5 delivers the gas mixture desired for the con templated treatment to the container.
  • the portion of the insulating sheath 6 extending into the container is provided, in the known manner, with a metallic shield 9 which is connected to the cover 2 on the one hand and, on the other, forms a protective gap together with the rod 7 in the known manner, the said gap preventing the penetration of the glow discharge towards the insulation 6.
  • This current lead-in 6, 7 and 9 is naturally fitted to the cover 2 so as to be gas-tight.
  • an additional electrode 10 which shields the workpiece 8 from the wall of the container and which here possesses, by way of example, cylindrical shape and is arranged coaxially with the cylinder 8.
  • This additional electrode 10 is insulated relative to the container wall on all sides.
  • the electrode 10 rests, on several insulating components, on the base plate 3 of the container 1 of which only two are indicated in the drawing.
  • Such insulating supporting members are known (Swiss Patent 354,871) and may consist of a metallic sleeve 11 attached to the base plate 3 and carry an insulating tube 12 projecting over the lower rim of the metal sleeve 11 and holding a metal rod 13 attached to the electrode 10.
  • This rod 13 forms, together with the upper rim of the metal sleeve 11, a gap in the known manner so as to prevent the entry of the glow discharge as far as the insulating tube 12.
  • the electrode 10 which is here cylindrical and open at its upper and lower ends so as to facilitate the access of gas to the workpiece 8, has its upper end advantageously propped against the inside wall of the container by means of supporting members 14, 15.
  • Such insulating supporting members are known as well (Swiss Patent 373,114) so that a more detailed description may be dispensed with.
  • the electrode 10 must on all sides be electrically insulated relative to both the container 10 and the workpiece 8.
  • This additional metallic electrode 10 is connected to a current lead-in consisting of the metal sleeve 16, the insulating tube 17 and the metal rod 18, the said lead-in being arranged in gas-tight relationship with the cover 2 of the container 1.
  • a current source 19 is provided which may, by way of example, supply a direct voltage gradually or continuously adjustable between 400 and 1500 volts which should supply a power of about 50 kw. for the treatment of workpieces with a surface of up to 5000 cm.
  • the positive pole 20 of this current source 19 is commonly connected to the container, here to the cover 2, while the negative pole 21 is connected, via the metal rod 7, to the workpiece 8 which in the present case thus permanently forms the cathode of the glow discharge obtained.
  • the connections 20 and 21 of the current source 19 are additionally provided with a voltage divider and the metal rod 18 connected to the additional electrode 10 is equipped with the switch 24 having the three positions (a), (b) and (c).
  • the additional electrode 10 is without exterior connection and is thus fully insulated in the container 1.
  • the electrode 10 is connected to the central tap of the voltage divider 22, 23 and thus has a lower potential than the container 1 connected to the positive pole 20 of the current source 19.
  • the electrode is also connected to the positive pole of the current source 19 and is thus under the same potential as the container 1.
  • the device according to the embodiment disclosed enables workpieces to be treated in any atmosphere desired within the container 1 according to a simplified process.
  • the switch 24 may eg be placed in its position (a).
  • the electrode 10 is then without any electrical connection with the container 1; nonetheless a glow discharge, though weak, occurs between the container wall and the workpiece 8, the said glow discharge producing a plasma within the container.
  • This plasma results in that the electrode 10 assumes a certain positive potential and that a glow discharge of comparatively low energy is obtained between the electrode 10 and the workpiece 8.
  • the intensity of the current of discharge for this weak glow discharge in the said first space of time is limited by the fact that the electrode in its turn obtains the current of discharge, via the plasma, from the walls of the container 1. So if imperfections of the surfaces of the workpiece 8 cause a tendency of the glow discharge towards arcing, such arcing cannot form because the current necessary therefor is not supplied by the electrode 10 and the potential of the electrode 10 drops accordingly, possibly causing a brief interruption of the glow discharge.
  • the switch 24 may be turned, by way of example, to its position (b) in which the electrode 10 obtains a potential dependent on the ratio of the resistances '22, 23 and lower than that of the container 1, appropriate selection of the resistances 22, 23 making it possible for the energy of discharge to suflice to raise the workpiece 8 to the necessary temperature.
  • the switch 24 may then be thrown into its position (c) in which the electrode 10 receives the same potential as the container 1 and is directly connected to the positive pole 20 of the current source 19.
  • the treatment of the workpiece 8 can then' be performed in the glow discharge at full energy.
  • such a fast-action switch may advantageously be employed to actuate the switch 24 from its position (c) into the position (b) or (a) so that the energy of the discharge caused between the workpiece 8 and the electrode 10 is substantially reduced and a rise of the current of discharge to the value necessary for the formation of an are or fiashover is prevented.
  • This measure which necessitates merely a switch-over of the connection of the electrode 10 must more readily be taken than the disconnection of the current source and can naturally be effected inertialessly if the mechanical switch 24 shown diagrammatically is replaced by an electronic switch of known design.
  • the present method enables the power delivery to the workpiece '8 to be particularly simply adjusted during the treatment process proper.
  • the temperature of the surface of the workpiece 8 treated by inconporated thermocouple elements or other measuring instruments and the operating voltage of the current source 19 to be so influenced that the prescribed temperature is maintained within the tolerances given.
  • This monitoring and influencing of the workpiece temperature can be substantially simplified in the present method in that the switch 24, which is in its position (c) during the actual treatment process is thrown to position (b) or (a) when the workpiece temperature rises inadmissibly until the said temperature has again reached the predetermined level, whereupon the switch 24 is again thrown to position (c).
  • Such switching may as well be effected by known electronic means, virtually inertialess and at very little expense.
  • a direct current source 19 is indicated.
  • the method is naturally not limited thereto but may be performed in the same manner using an alternating current source.
  • three workpieces are treated simultaneously in a common container, the said workpieces being supplied by the three phases of a three-phase current source of which the neutral point is connected to the container; in that case, too, the present method may be performed.
  • only a single additional electrode need be arranged in the container which effects shielding of the three workpieces from the container and is used to control the discharge energy analogously with the method above described.
  • a voltage divider formed by the resistance 22, 23 is provided between the poles 20, 21 of the current source 19; if so desired, voltage division may be dispensed with and the resistance 22 omitted so that only the series resistance 23 is located in the circuit of the electrode 10. Mention should also be made of the fact that, in the operation with direct current as shown in FIG. 1, glow discharge does not occur at either the additional electrode or the container wall; for this reason the insulating supports 11, 12, 13 and 14, may also be simplified and designed without a protective gap system.
  • FIG. 2 shows a different embodiment of the device disclosed with reference to FIG. 1, similar components being designated by the same reference numerals.
  • the additional electrode '10 is here designed as a cage and, in the present embodiment, consists of the upper and lower metal rings 30 and 31 both shown in section and twelve metallic connecting bars 32 rotatably attached to the said metal rings 30, 31.
  • 'Each connecting bar 32 carries a metallic wing 33 which, in the position of the connecting bars 32 shown in FIG. 2, form a metallic cylinder which is as closed as possible.
  • Rotation of the connecting bars 32 enables the individual wings 33 to be swung outwards.
  • each of the twelve connecting bars 32 can therefore be turned by means of its own rigid lever 34 and a pivot bearing 35 with the adjusting ring 36 of which movement in the direction of the arrow 37 causes all wings 33 to be swung out.
  • actuation of the adjustment ring 36 in operation is contemplated to which end a pin 39 is provided on the adjustment ring 36 which projects into the gap between the two prongs of a fork 38 which can be rotated by means of the shaft 41'through a lead-in 40 which is electrically insulated relative to the container 1.
  • a pin 39 is provided on the adjustment ring 36 which projects into the gap between the two prongs of a fork 38 which can be rotated by means of the shaft 41'through a lead-in 40 which is electrically insulated relative to the container 1.
  • the wings 33 of the additional electrode 10 are advantageously positioned tangentially so as to form, together with the connecting bars 32, an almost closed cylindrical surface. Since the wings 33 advantageously have a polished surface inside, the heat radiated from the workpiece 8 is largely reflected back to the same so that the relatively small energy of discharge suflices to bring the workpiece 8 to the desired temperature. If it proves to be of advantage to reduce the reflecting surface of the electrode 10, the wings 33 may be swung out more or less 6 from their tangential position. However, it should at all times be ensured that the glow discharge occurs largely between the workpiece 8 and the electrode 10 and not on the inside of the container 1.
  • the workpiece 8 is treated with the least possible consumption of energy since only such energy need be supplied as ensures the maintenance of the prescribed elevated temperature of the surface of the workpiece 8.
  • heat reflection by the electrode 10 is reduced so that the necessary increase in the energy of discharge must be effected for the maintenance of the prescribed temperature of the workpiece surface.
  • the said heat losses may be quite variable since they depend on the radiating capacity of the workpiece surface and, respectively, the inside of the container so that treatment must be effected with correspondingly diiferent energies of discharge, which may result in quality differences in the workpiece surfaces.
  • the present device enables both the temperature and the energy of discharge to be prescribed and the maintenance of temperature to be ensured by modification of the heat reflection of the additional electrode.
  • the additional electrode which may have its surface adjusted, may naturally be employed also if the device is run, as previously described, on alternating or threephase current.
  • FIG. 4 A further embodiment of an additional electrode 10 with a plurality of adjustable surface sections is shown diagrammatically in FIG. 4.
  • the additional electrode here consists of two superposed groups 45 and 46 formed of adjustable wings which are designed in a manner similar to that shown in FIGS. 2 and 3, Le. of wings attached to rotatable bars.
  • the wings of the groups 45 and 46 may be provided with adjusting means which can be separately actuated.
  • Further Wings 47 may be provided which can be adjusted independently of the two groups 45 or 46, such wings enabling more or less intense reflection of the bottom of the container to be obtained.
  • the adjustment of the wings of the additional electrode is effected via a fork 38 insulatedly passed through the container wall located on the shaft 41.
  • Other suitable actuating means are naturally possible.
  • the shaft 41 need not be electrically insulated relative to the container 1 if the pin 39 is formed of an insulating material or if the fork 38 is replaced by an eccentrically designed disc formed of a nonconductive material. It is also possible to employ adjustment means which are magnetically operated.
  • the wings of the additional electrode shown in Figs. 2 through 4 are represented as curved shells which, in their tangential final position, form a largely closed cylinder electrode together. In the presence of a sufficiently large number of wings or of a sufficiently large diameter of the additional electrode, fiat wings may naturally be employed as well.
  • a method according to claim 1 characterized in that, during the second space of time, the electrical connection between the electrode and the container is broken during an adjustable interval of time whenever the energy of the glow discharge must be reduced.
  • a method according to claim 4 characterized in that a plurality of surface components of the additional electrode are simultaneously displaced in the same direction to alter said heat-reflecting surface.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Plasma & Fusion (AREA)
  • Analytical Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Discharge Heating (AREA)
US00114162A 1970-02-13 1971-02-10 Method of treating workpieces in a glow discharge Expired - Lifetime US3730863A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH209370A CH519588A (de) 1970-02-13 1970-02-13 Verfahren zur Bearbeitung eines Werkstückes mittels einer Glimmentladung und Apparatur zur Durchführung des Verfahrens
CH4271A CH555898A (de) 1970-02-13 1971-01-05 Verfahren zur bearbeitung eines werkstueckes mittels einer glimmentladung und apparatur zur durchfuehrung des verfahrens.

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US00114162A Expired - Lifetime US3730863A (en) 1970-02-13 1971-02-10 Method of treating workpieces in a glow discharge

Country Status (11)

Country Link
US (1) US3730863A (de)
JP (1) JPS5118895B1 (de)
AT (1) AT303904B (de)
BE (1) BE762430A (de)
CA (1) CA970327A (de)
CH (2) CH519588A (de)
DE (1) DE2106850C3 (de)
FR (1) FR2078067A5 (de)
LU (1) LU62593A1 (de)
NL (1) NL7101947A (de)
SE (1) SE358907B (de)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3863074A (en) * 1972-08-30 1975-01-28 Ibm Low temperature plasma anodization apparatus
US3973132A (en) * 1974-04-27 1976-08-03 Softal Elektronik Gmbh Apparatus for the treatment of non-conductive foils or like thin sheeting
JPS527337A (en) * 1975-07-08 1977-01-20 Fuji Electronics Co Ltd Ion surface treatment of metal
US4019064A (en) * 1974-03-19 1977-04-19 Henri Michel High intensity ionic bombardment reactor for thermochemical treatment processes
US4124199A (en) * 1977-07-11 1978-11-07 Abar Corporation Process and apparatus for case hardening of ferrous metal work pieces
US4193825A (en) * 1977-06-28 1980-03-18 Kayaba Industry Co., Ltd. Method of carbon nitriding a metal workpiece
US4221972A (en) * 1978-01-26 1980-09-09 Werner Oppel Apparatus for the partial treatment of elongated articles by current intensive glow discharge
US4242151A (en) * 1978-10-25 1980-12-30 Creusot-Loire Chromizing of steels by gaseous method
US4298629A (en) * 1979-03-09 1981-11-03 Fujitsu Limited Method for forming a nitride insulating film on a silicon semiconductor substrate surface by direct nitridation
US4309227A (en) * 1978-07-14 1982-01-05 Kawasaki Jukogyo Kabushiki Kaisha Ion-nitriding process
US4342918A (en) * 1975-12-29 1982-08-03 Kawasaki Jukogyo Kabushiki Kaisha Ion-nitriding apparatus
US4349403A (en) * 1981-01-16 1982-09-14 Lord Corporation Method for bonding elastomers to steel
US4357182A (en) * 1980-05-29 1982-11-02 Creusot-Loire Chromization of steels by gas process
US4394234A (en) * 1979-02-02 1983-07-19 Hitachi, Ltd. Method of processing electrically conductive material by glow discharge
US4404076A (en) * 1978-12-28 1983-09-13 Canon Kabushiki Kaisha Film forming process utilizing discharge
US5989363A (en) * 1997-04-18 1999-11-23 Plasma Metal Sa Nitriding process and nitriding furnace therefor
CN105115801A (zh) * 2015-09-11 2015-12-02 贵州省分析测试研究院 一种金属材料分析前处理器
US10443117B2 (en) * 2013-12-18 2019-10-15 Ihi Corporation Plasma nitriding apparatus
US20220216649A1 (en) * 2019-04-10 2022-07-07 Icotek Project Gmbh & Co. Kg Device for introducing cables through an opening
RU2777796C1 (ru) * 2021-11-29 2022-08-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Кубанский государственный технологический университет" (ФГБОУ ВО "КубГТУ") Устройство для азотирования в разряде

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH551496A (de) * 1970-09-21 1974-07-15 Berghaus Bernhard Elektrophysi Verfahren zur verfestigung der oberflaeche von werkstuecken aus eisen und stahl.
CH621714A5 (de) * 1976-06-08 1981-02-27 Balzers Hochvakuum
DE19601436A1 (de) * 1996-01-17 1997-07-24 Siegfried Dr Ing Straemke Verfahren und Vorrichtung zur Oberflächenbehandlung von Werkstücken

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3863074A (en) * 1972-08-30 1975-01-28 Ibm Low temperature plasma anodization apparatus
US4019064A (en) * 1974-03-19 1977-04-19 Henri Michel High intensity ionic bombardment reactor for thermochemical treatment processes
US3973132A (en) * 1974-04-27 1976-08-03 Softal Elektronik Gmbh Apparatus for the treatment of non-conductive foils or like thin sheeting
JPS527337A (en) * 1975-07-08 1977-01-20 Fuji Electronics Co Ltd Ion surface treatment of metal
JPS5424897B2 (de) * 1975-07-08 1979-08-24
US4342918A (en) * 1975-12-29 1982-08-03 Kawasaki Jukogyo Kabushiki Kaisha Ion-nitriding apparatus
US4193825A (en) * 1977-06-28 1980-03-18 Kayaba Industry Co., Ltd. Method of carbon nitriding a metal workpiece
US4124199A (en) * 1977-07-11 1978-11-07 Abar Corporation Process and apparatus for case hardening of ferrous metal work pieces
US4221972A (en) * 1978-01-26 1980-09-09 Werner Oppel Apparatus for the partial treatment of elongated articles by current intensive glow discharge
US4309227A (en) * 1978-07-14 1982-01-05 Kawasaki Jukogyo Kabushiki Kaisha Ion-nitriding process
US4242151A (en) * 1978-10-25 1980-12-30 Creusot-Loire Chromizing of steels by gaseous method
US4404076A (en) * 1978-12-28 1983-09-13 Canon Kabushiki Kaisha Film forming process utilizing discharge
US4394234A (en) * 1979-02-02 1983-07-19 Hitachi, Ltd. Method of processing electrically conductive material by glow discharge
US4298629A (en) * 1979-03-09 1981-11-03 Fujitsu Limited Method for forming a nitride insulating film on a silicon semiconductor substrate surface by direct nitridation
US4357182A (en) * 1980-05-29 1982-11-02 Creusot-Loire Chromization of steels by gas process
US4349403A (en) * 1981-01-16 1982-09-14 Lord Corporation Method for bonding elastomers to steel
US5989363A (en) * 1997-04-18 1999-11-23 Plasma Metal Sa Nitriding process and nitriding furnace therefor
US10443117B2 (en) * 2013-12-18 2019-10-15 Ihi Corporation Plasma nitriding apparatus
CN105115801A (zh) * 2015-09-11 2015-12-02 贵州省分析测试研究院 一种金属材料分析前处理器
CN105115801B (zh) * 2015-09-11 2019-01-22 贵州省分析测试研究院 一种金属材料分析前处理器
US20220216649A1 (en) * 2019-04-10 2022-07-07 Icotek Project Gmbh & Co. Kg Device for introducing cables through an opening
US12040574B2 (en) * 2019-04-10 2024-07-16 Icotek Project Gmbh & Co. Kg Device for introducing cables through an opening
RU2777796C1 (ru) * 2021-11-29 2022-08-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Кубанский государственный технологический университет" (ФГБОУ ВО "КубГТУ") Устройство для азотирования в разряде

Also Published As

Publication number Publication date
NL7101947A (de) 1971-08-17
CA970327A (en) 1975-07-01
BE762430A (fr) 1971-07-16
DE2106850C3 (de) 1974-01-31
CH555898A (de) 1974-11-15
FR2078067A5 (de) 1971-11-05
LU62593A1 (de) 1971-08-19
AT303904B (de) 1972-12-11
SE358907B (de) 1973-08-13
DE2106850B2 (de) 1973-07-05
JPS5118895B1 (de) 1976-06-14
CH519588A (de) 1972-02-29
DE2106850A1 (de) 1971-12-16

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