FR2544748A2 - Process for producing a protective oxide layer - Google Patents

Process for producing a protective oxide layer Download PDF

Info

Publication number
FR2544748A2
FR2544748A2 FR8306647A FR8306647A FR2544748A2 FR 2544748 A2 FR2544748 A2 FR 2544748A2 FR 8306647 A FR8306647 A FR 8306647A FR 8306647 A FR8306647 A FR 8306647A FR 2544748 A2 FR2544748 A2 FR 2544748A2
Authority
FR
France
Prior art keywords
mbar
oxidation
subjected
oxide layer
water vapor
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.)
Pending
Application number
FR8306647A
Other languages
French (fr)
Inventor
Hans Zeilinger
August Muhlratzer
Bruno Stemmler
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MAN AG
Original Assignee
MAN Maschinenfabrik Augsburg Nuernberg AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE19813108160 external-priority patent/DE3108160C2/en
Priority claimed from DE3215314A external-priority patent/DE3215314C2/en
Application filed by MAN Maschinenfabrik Augsburg Nuernberg AG filed Critical MAN Maschinenfabrik Augsburg Nuernberg AG
Publication of FR2544748A2 publication Critical patent/FR2544748A2/en
Pending legal-status Critical Current

Links

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
    • C23C8/08—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
    • C23C8/10—Oxidising
    • C23C8/16—Oxidising using oxygen-containing compounds, e.g. water, carbon dioxide
    • 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
    • C23C8/02—Pretreatment of the material to be coated
    • 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
    • C23C8/10—Oxidising
    • C23C8/16—Oxidising using oxygen-containing compounds, e.g. water, carbon dioxide
    • C23C8/18—Oxidising of ferrous surfaces

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Chemical Treatment Of Metals (AREA)

Abstract

The technical field of the invention relates to the processes for obtaining resistant oxide layers on objects made of titanium-based alloy. The technical problem posed consists in finding the succession of mechanical and chemical treatments making it possible to control the formation of a resistant oxide layer. According to the invention such a process comprises a pretreatment followed by an oxidation by application of a low oxidation potential and a temperature of between 500 and 900 DEG C. The oxidising agent employed is preferably steam at a partial pressure of approximately 20 mbar. The invention finds a main use in that the oxide layer obtained offers good protection against friction welding in the case of articles made of titanium-based alloy subjected to high stresses (especially in turbines and compressors).

Description

"Procédé de réalisation de couche d'oxyde protectrice."Process for producing a protective oxide layer.

L'invention a pour objet un procédé pour réaliser des couches d'oxyde protectrices sur un objet méral- lique, dans lequel on soumet l'objet, après un traitement préliminaire, à un processus d'oxydation à température élevée, comme décrit dans le brevet principal. The subject of the invention is a process for producing protective oxide layers on a metallic object, in which the object is subjected, after a preliminary treatment, to an oxidation process at high temperature, as described in the main patent.

On connait la protection apportée par tes couches d'oxydes sur les objets métalliques contre des oxyde tion ou des corrosions ultérieures. D'autre part, les couches d'oxydes naturelles ou constituées par des procédés connus préviennent, dans une certaine mesure, le soudage par friction entre des surfaces de contact, quand la charge n'est pas forte ou qu'il existe un film de lubrifiant. Il n'existe aucune fiabilite sur la durée de la résistance dans le cas d'une surface de contact sèche sous forte contrainte, par exemple des vibrations haute fréquence. Sous de telles conditions apparait généralement rapidement le soudage par friction et il en résulte que l'on ne peut plus débloquer la liaison. We know the protection provided by your layers of oxides on metal objects against oxidation tion or subsequent corrosion. On the other hand, the layers of natural oxides or formed by known methods prevent, to a certain extent, friction welding between contact surfaces, when the load is not strong or when there is a film of lubricant. There is no reliability over the duration of the resistance in the case of a dry contact surface under high stress, for example high frequency vibrations. Under such conditions, friction welding generally appears quickly, and as a result, the connection can no longer be released.

Sont particulièrement concernées les liaisons entre éléments en titane ou alliage à base de titane soumises aux contraintes mentionnées ci-dessus dans les turbines et les compresseurs. Particularly concerned are the connections between titanium or titanium-based alloy elements subject to the constraints mentioned above in turbines and compressors.

Une méthode connue, pour protéger les objets en titane contre le soudage par friction , consiste en ce que 'on recouvre la surface de ces objets avec ue couche d'oxyde. A known method for protecting titanium objects against friction welding consists in covering the surface of these objects with an oxide layer.

Suivant le procédé connu, la couche en oxyde de titane (TiO2) est obtenue en chauffant l'objet dans une atmosphère d'oxygène pur,
Un tel procédé ne permet néanmoins pas d'ase surer une protection des objets dans le cas de contraintes extremes, notamment sous des températures élevées, comme il arrive dans les compresseurs et les turbines.According to the known process, the titanium oxide (TiO2) layer is obtained by heating the object in an atmosphere of pure oxygen,
Such a method does not, however, allow safe protection of objects in the case of extreme stresses, in particular under high temperatures, as happens in compressors and turbines.

Les couches obtenues par le procédé connu ne présentent aucune stabilité mécanique suffisante et donc auxune résistance satisfaisante contre le souda@@ par friction. La couche de protection se brise dès l'apparition de faibles sollicitations, s'en va par endroits, et est donc en relativement peu de temps complètement détruite et hors d'usage. The layers obtained by the known method have no sufficient mechanical stability and therefore have a satisfactory resistance against soda @ @ by friction. The protective layer breaks when low stresses appear, goes away in places, and is therefore in a relatively short time completely destroyed and out of use.

En application de l'invention selon la demand@ do brevet princlpal, l'amélioration apportée a procédé connu décrit ci-dessus consiste à permettre à la couche d'oxyde d'assurer une protection pleinement opérante contre la soudure par friction dans le cas de liaisons de pièces de machines en alliage à base de titane.  In application of the invention according to the main patent demand @ do, the improvement made to the known process described above consists in allowing the oxide layer to provide fully effective protection against friction welding in the case of connections of titanium-based alloy machine parts.

La solution, selon la demande de brevet principal, consiste , pour l'application du procédé à des objets en acier allié au chrome et au nickel, en ce que l'on soumet l'objet à un traitement préalable mécanique et/ou chimique et en ce que l'on effectue le processus d'oxydation qui suit en utilisant un potentiel d'oxydation plus faible et une température comprise entre 500 et 9000C environ.La présente invention utilise ce meme procédé, décrit selon la revendication 1, dans une autre forme d'application
en effet, il est également possible d'effectuer une oxydation sélective au moyen d'un potentiel d'oxyde tion plus faible, grâce auquel par le choix d'une pression partielle adéquate de l'agent d'oxydation, on peut obtenir que quelques éléments seulement, composant la matiè@e de l'obje@, et de préférence un seul élément, soient oxydés.Il en résul que pour un métal qui peut former des oxydes différents cor respondant à des niveaux différents de valence, on peut velon- tairement ne former que les oxydes de valence faible Dans e cas présent il s'agit du Ti2O3, qui est isotope du A12OS dont les propriétés mécaniques interessantes sont bien connues et qui l'ont amené à etre largement utilisé sous Ja for- me de couche de protection contre l'usure,au moye du procé- dé C.V.D.The solution, according to the main patent application, consists, for the application of the process to steel objects alloyed with chromium and nickel, in that the object is subjected to a mechanical and / or chemical prior treatment and in that the following oxidation process is carried out using a lower oxidation potential and a temperature of between 500 and 9000C approximately. The present invention uses this same process, described according to claim 1, in another form of application
indeed, it is also possible to carry out a selective oxidation by means of a lower oxidation potential, thanks to which by the choice of an adequate partial pressure of the oxidizing agent, it is possible to obtain only a few only elements, composing the material of the object, and preferably only one element, are oxidized. It follows that for a metal which can form different oxides corresponding to different levels of valence, one can velon- taire only form oxides of low valence In this case it is Ti2O3, which is isotope of A12OS whose interesting mechanical properties are well known and which have led it to be widely used in Ja form of layer wear protection, using CVD process

Un avantage remarquable du- procédé selon l'in- vention réside donc en ce que des couches peuvent être obtenues qui présentent un mélange homogène de Tri 203 et Al2O3 et égaiement de tTi,Al)03. Ce mélange présente d'une part une haute résistance à l'usure, et autre part un faible coefficient de frottement. En conséquence, et grâce au fait que le procédé selon l'invention permet d'obtenir des couches d'épaisseur régulière, ainsi qu'une stabilité mécanique ameliorée par rap- port à l'état de la technique, ces couches constituent une bonne protection contre la soudure par friction, égalemen dans les hautes températures. A remarkable advantage of the process according to the invention therefore lies in the fact that layers can be obtained which have a homogeneous mixture of Tri 203 and Al2O3 and also of tTi, Al) 03. This mixture has on the one hand a high resistance to wear, and on the other hand a low coefficient of friction. Consequently, and thanks to the fact that the method according to the invention makes it possible to obtain layers of regular thickness, as well as improved mechanical stability compared with the state of the art, these layers constitute good protection. against friction welding, also in high temperatures.

La qualité de la couche de protection peut être encore davantage améliorée si l'on soumet l'objet à un traitement préalable mécanique, comme par exemple un formage à froid. Ce traitement mécanique, qui peut être un meulage, un pierrage, un laminage, ou un grenaillage, suivi éventuellement d'un polissage, permet d'obtenir une amélioration de la finesse du grain en surface de l'objet en fonction du traite- ment thermique postérieur, et par là une augmentation de la mobilité des atomes de l'alliage, mobilité nécessaire pour que les composés minoritaires de 1'aluminium s'insèrent dans 1'o- xyde. I1 en résulte une adhérence améliorée.Cette bonne sta- bilité mécanique se fonde également sur la formation mentionnée ci-dessus de (Ti,Al)203 grâce au potentiel d'oxydation faible, formation lente mais dense à cause de la faible vitesse de diffusion dans le réseau cristallin. The quality of the protective layer can be further improved if the object is subjected to a mechanical preliminary treatment, such as for example cold forming. This mechanical treatment, which can be grinding, honing, rolling, or shot peening, possibly followed by polishing, makes it possible to obtain an improvement in the fineness of the grain on the surface of the object as a function of the treatment. posterior thermal, and thereby an increase in the mobility of the atoms of the alloy, mobility necessary for the minority aluminum compounds to be inserted into the oxide. This results in improved adhesion. This good mechanical stability is also based on the above-mentioned formation of (Ti, Al) 203 thanks to the low oxidation potential, slow but dense formation due to the low diffusion rate. in the crystal lattice.

Le C02 peut être utilisé comme agent d'oxyda tion pendant le processus d'@xydation. On peut alors utiliser le mélange gazeux tampon 2C02= 2CO+O2 poux abaisser la pression partielle en oxygène. CO2 can be used as an oxidizing agent during the oxidation process. The buffer gas mixture 2C02 = 2CO + O2 can then be used to lower the partial oxygen pressure.

Un agent préférentiel d'oxydation est la vapeur d'eau. Dans le cas de la vapeur d'eau et au moyen du mélange gazeux tampon 2H20 = 2H2+O2, on peut obtenir un potentiel d'oxydation encore plus faible que dans le cas du C02. De plus, l'hydrogène libéré pendant l'opération d'oxydation joue un rôle positif sur le processus, par le fait que cet oxygène produit à l'inter phase une réduction supplémentaire de la pression partielle en oxygène.  A preferred oxidizing agent is water vapor. In the case of water vapor and by means of the buffer gas mixture 2H20 = 2H2 + O2, an even lower oxidation potential can be obtained than in the case of C02. In addition, the hydrogen released during the oxidation operation plays a positive role in the process, by the fact that this oxygen produces in the inter phase an additional reduction of the partial oxygen pressure.

Pour réaliser le processus d'oxydation sous une pression réduite et dans le but d'éviter l'utilisation d'appareils à vide , il est proposé d'amener l'agent d'oxydation sur l'objet à couvrir d'une couche d'oxyde da3 un gaz porteur inerte, de préférence un gaz rare, particuliè rement l'hélium ou l'argon. L'agent d'oxydation peut êtro alors et ae préférence utilisé dans un circuit fermé, ou s--en également dans un système de circulation semi-fermé ou à l'air libre. To carry out the oxidation process under reduced pressure and in order to avoid the use of vacuum devices, it is proposed to bring the oxidizing agent to the object to be covered with a layer of oxide of an inert carrier gas, preferably a rare gas, particularly helium or argon. The oxidizing agent can then be preferably used in a closed circuit, or also in a semi-closed circulation system or in the open air.

Dans le cas de l'utilisation du CO2 comme agent d'oxydation, le potentiel d'oxydation requis est infé- rieur à 50 mbar , de préférence aux environs de 10 mbar dans le cas de la vapeur d'eau, la pression partielle est inférieure à 100 mbar , ces valeurs s'entendant dans les eonditions normales. Avantageusement, le processus d'oxydation sera mené avec la vapeur d'eau à une pression partielle d'environ 20 mbar . Dans ce dernier cas, on travaille directement à la pression atmospherique et à la température ambiante. When using CO2 as an oxidizing agent, the required oxidation potential is less than 50 mbar, preferably around 10 mbar in the case of water vapor, the partial pressure is less than 100 mbar, these values being understood under normal conditions. Advantageously, the oxidation process will be carried out with water vapor at a partial pressure of around 20 mbar. In the latter case, one works directly at atmospheric pressure and at ambient temperature.

De préférence, l'épaisseur de la couche d'oxyde mesure entre 10 et 15 microns. Une telle couche est résistante et par suite stable sous les efforts mécaniques et autres sollicitations. Preferably, the thickness of the oxide layer measures between 10 and 15 microns. Such a layer is resistant and consequently stable under mechanical stresses and other stresses.

EXEMPLE DE REALISATION
EXEMPLE I
Pour recouvrir d'une couche d'oxyde un alliage à base de titane TiAl6V4 on a procédé aux étapes suivantes
a) la surface a tout d'abord suivi les traitements mécaniques de meulage (granulation 320), de honing ou grenaillage, puis de polissage au contact d'autres pièces.EXAMPLE OF IMPLEMENTATION
EXAMPLE I
The following steps were taken to cover a titanium-based alloy TiAl6V4 with an oxide layer.
a) the surface first of all followed the mechanical grinding (granulation 320), honing or shot blasting treatments, then polishing in contact with other parts.

b) Le processus d'oxydation a ensuite été mené par 8000C avec 20 mbar de vapeur d'eau dans l'argon
c) Après quatre heures d'un tel processus d'oxydation, on a obtenu une couche de Wi,Al)203 de 10 à 15 microns. b) The oxidation process was then carried out by 8000C with 20 mbar of water vapor in argon
c) After four hours of such an oxidation process, a layer of Wi, Al) 203 of 10 to 15 microns was obtained.

Claims (10)

REVENDICATIONS 10) Procédé de réalisation de couches d'oxydes protectrices sur des objets soumis, après traitement préliminaire, à un processus d'oxydation sous température élevée, selon l'une quelconque des revendications 1 et 4 à 10 du brevet principal, caractérisé en ce que, pour l'application du procédé à des objets en alliage à base de titane, on soumet l'objet à un traitement préalable mécanique et/ou chimique, et en ce que l'on effectue le processus d'oxydation qui suit en utilisant un potentiel d'oxydation plus faible et une température comprise entre 500 et 9000C.  10) Process for producing protective oxide layers on objects subjected, after preliminary treatment, to an oxidation process under elevated temperature, according to any one of claims 1 and 4 to 10 of the main patent, characterized in that , for the application of the process to titanium-based alloy objects, the object is subjected to a mechanical and / or chemical preliminary treatment, and in that the following oxidation process is carried out using a lower oxidation potential and a temperature between 500 and 9000C. 20) Procédé selon la revendication 1, caractérisé en ce que l'on procède à un traitement mécanique préalable, particulièrement un écrouissage. 20) Method according to claim 1, characterized in that one proceeds to a prior mechanical treatment, particularly work hardening. 30) Procédé selon l'une des revendications i et 2, caractérisé en ce que l'objet, après traitement préalable, est soumis à un processus d'oxydation sous un potentiel d'oxydation faible au moyen d'un mélange gazeux tampon comprenant de l'oxygène. 30) Method according to one of claims i and 2, characterized in that the object, after prior treatment, is subjected to an oxidation process under a low oxidation potential by means of a gaseous buffer mixture comprising oxygen. 40) Procédé selon la revendication 3, caractérisé en ce que la pression partielle en CO2, rapportée aux conditions normales, est inférieure à 50 mbar , de préférence aux environs de 10 mbar 40) Method according to claim 3, characterized in that the partial pressure of CO2, relative to normal conditions, is less than 50 mbar, preferably around 10 mbar 50) Procédé selon l'une quelconque des revendications de 1 à 4, caractérisé en ce que l'agent d'oxydation est de la vapeur d'eau. 50) A method according to any one of claims 1 to 4, characterized in that the oxidizing agent is water vapor. 60) Procédé selon la revendication 5, caractérisé en ce que la pression partielle en vapeur d'eau, rame- née aux conditions normales, est inférieure à 100 mbar , de préférence aux environs de 20 mbar 60) Method according to claim 5, characterized in that the partial pressure of water vapor, returned to normal conditions, is less than 100 mbar, preferably around 20 mbar 7 ) Procédé selon l'une quelconque des revendications 3 à 6, caractérise en ee que 'agent d'oxydatioll est conduit sur l'objet à revêtir au moyen d'un gaz porteur inerte, de préférence un gaz rare tei que l'argon ou l'hélium. 7) Method according to any one of claims 3 to 6, characterized in that the oxidizing agent is conducted on the object to be coated by means of an inert carrier gas, preferably a rare gas such as argon or helium. 80) Procédé selon l'une quelconque des revendications 1 à 7, caractérisé en ne que la durée d'oxydation est comprise entre 2 et 8 heures  80) Method according to any one of claims 1 to 7, characterized in that the oxidation time is between 2 and 8 hours 90) Procédé selon l'une quelc@ ie des revendications 1 à 8, caractérisé en ce que l'épaisseur de la couche oxydée est comprise entre 10 et 15 microns. 90) Method according to any of claims 1 to 8, characterized in that the thickness of the oxidized layer is between 10 and 15 microns. 100) Procédé selon l'une quelconque des revendications 1 à 9, caractérisé en ce que, après un traitement méca@ique préalable, on soumet l'objet à un processus d'oxydation pendant environ 4 heures à 800 sous 20 mbar de pression de vapeur d'eau portée dans un gaz rare  100) Method according to any one of claims 1 to 9, characterized in that, after a prior mechanical treatment, the object is subjected to an oxidation process for about 4 hours at 800 at 20 mbar pressure of water vapor carried in a rare gas
FR8306647A 1981-02-06 1983-04-22 Process for producing a protective oxide layer Pending FR2544748A2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE3104111 1981-02-06
DE19813108160 DE3108160C2 (en) 1981-02-06 1981-03-04 Process for the production of oxide layers on chrome and / or nickel alloy steels
DE3215314A DE3215314C2 (en) 1982-04-23 1982-04-23 Process for the production of oxide layers on a titanium-based alloy surface

Publications (1)

Publication Number Publication Date
FR2544748A2 true FR2544748A2 (en) 1984-10-26

Family

ID=27189126

Family Applications (1)

Application Number Title Priority Date Filing Date
FR8306647A Pending FR2544748A2 (en) 1981-02-06 1983-04-22 Process for producing a protective oxide layer

Country Status (1)

Country Link
FR (1) FR2544748A2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2588203A1 (en) * 1985-10-08 1987-04-10 Hauni Werke Koerber & Co Kg RETAINER OR SUPPORT FOR PARTS, PARTICULARLY FOR TURBINE BLADES

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1188302B (en) * 1962-06-23 1965-03-04 Titan Gmbh Process for uniform hardening of titanium sponge
JPS5573876A (en) * 1978-11-21 1980-06-03 Sumitomo Metal Ind Ltd Improving method for antioxidizing property of cr-containing steel
FR2465788A1 (en) * 1979-09-19 1981-03-27 Hermsdorf Keramik Veb Wear resistant components for mixing or milling plant - esp. rollers or balls, which are coated with titanium contg. specific amts. of oxygen and nitrogen

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1188302B (en) * 1962-06-23 1965-03-04 Titan Gmbh Process for uniform hardening of titanium sponge
JPS5573876A (en) * 1978-11-21 1980-06-03 Sumitomo Metal Ind Ltd Improving method for antioxidizing property of cr-containing steel
FR2465788A1 (en) * 1979-09-19 1981-03-27 Hermsdorf Keramik Veb Wear resistant components for mixing or milling plant - esp. rollers or balls, which are coated with titanium contg. specific amts. of oxygen and nitrogen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENTS ABSTRACTS OF JAPAN, vol. 4, no. 119, (C-22)(601), page 51C21, 23 août 1980, & JP - A - 55 73 876 (SUMITOMO KINZOKU KOGYO KK)(03-06-1980). *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2588203A1 (en) * 1985-10-08 1987-04-10 Hauni Werke Koerber & Co Kg RETAINER OR SUPPORT FOR PARTS, PARTICULARLY FOR TURBINE BLADES

Similar Documents

Publication Publication Date Title
FR2474533A1 (en) HEAT-RESISTANT MECHANICAL PIECE AND PROCESS FOR PREPARING THE SAME
US4478648A (en) Method of producing protective oxide layers
FR2607840A1 (en) METHOD AND DEVICE FOR COATING CARBON FIBERS WITH CARBIDE AND CARBON FIBERS THUS COATED
FR2499593A1 (en) PROCESS FOR MAKING PROTECTIVE OXIDE LAYERS
FR2654786A1 (en) COMPOSITE FRICTION MATERIAL FOR BRAKES.
LU86916A1 (en) Oxidation-resistant carbon and process for its manufacture.
FR2660938A1 (en) COATING SYSTEMS FOR TITANIUM PROTECTION AGAINST OXIDATION.
FR2598644A1 (en) THERMOSTABLE DIAMOND ABRASIVE PRODUCT AND PROCESS FOR PRODUCING SUCH A PRODUCT
EP0884403A1 (en) Multilayer material with erosion/wear/corrosion protective coating on a substrate of aluminium, magnesium and their alloys
BE898043A (en) PROCESS FOR ESTABLISHING A PROTECTIVE LAYER BY DIFFUSION ON ALLOYS BASED ON COBALT NICKEL AND / OR IRON.
LU87236A1 (en) Coated ceramic fillers.
FR2499592A1 (en) PROCESS FOR MAKING PROTECTIVE OXIDE LAYERS
FR2624882A1 (en) PROCESS FOR COATING TITANIUM ALLOY PARTS WITH DIFFUSED ALUMINUM
EP0738787B1 (en) Method of making a metal object covered with diamond
FR2620734A1 (en) MULTIPHASE REFRACTORY METAL ALLOY, OXYCARBON OR OXYCARBONITRIDE, WITH PROGRESSIVE VARIATION IN HARDNESS FROM THE SURFACE
FR2680505A1 (en) PROCESS FOR MANUFACTURING A GRAPHITE MOLDED BODY.
FR2522543A1 (en) PROCESS FOR APPLYING A COMPOSITE MATERIAL COATING ON PARTS
EP0077703B1 (en) Chromium-based wear resistant coating for steel and process for producing the same
FR2544748A2 (en) Process for producing a protective oxide layer
FR2787472A1 (en) PROCESS FOR PRODUCING A METALLIC ALLOY POWDER OF THE MCRALY TYPE AND COATINGS OBTAINED THEREWITH
FR2546448A1 (en) COATED METALLIC OBJECT AND METHOD FOR MANUFACTURING THE SAME
FR2576916A1 (en) Process for forming protective coatings on articles made of refractory alloys in a constantly renewed gas phase, under reduced pressure, and device for its implementation
FR2714049A1 (en) Improvements made to structural products.
EP0885980B1 (en) Process for forming a superficial layer having a high hardness by plasma-free thermochemical treatment
EP0067098A1 (en) Method of ionitriding a steel article which has been plastically deformed in advance