EP0015807A1 - Process for manufacturing a radioactive source and radioactive source thus obtained - Google Patents

Process for manufacturing a radioactive source and radioactive source thus obtained Download PDF

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Publication number
EP0015807A1
EP0015807A1 EP19800400238 EP80400238A EP0015807A1 EP 0015807 A1 EP0015807 A1 EP 0015807A1 EP 19800400238 EP19800400238 EP 19800400238 EP 80400238 A EP80400238 A EP 80400238A EP 0015807 A1 EP0015807 A1 EP 0015807A1
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Prior art keywords
layer
substrate
radio
source
deposited
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German (de)
French (fr)
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EP0015807B1 (en
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Jean-Pierre Galmiche
Francine Moser
Denise Remy
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Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
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Commissariat a lEnergie Atomique CEA
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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21G—CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES
    • G21G4/00—Radioactive sources
    • G21G4/04—Radioactive sources other than neutron sources
    • G21G4/06—Radioactive sources other than neutron sources characterised by constructional features

Definitions

  • the present invention relates to a method for manufacturing a radioactive source and the source obtained by said method.
  • French patent 2,279,206 discloses a process for producing sources of ionizing radiation according to which an active layer of a radio-element is deposited on a nickel substrate, and then the substrate thus coated is subjected to a heat treatment. so as to cause the formation of an inactive layer of nickel oxide allowing the protection of the active layer of radio-element, this nickel oxide being formed by oxidation of nickel which constitutes the substrate and which has diffused through the layers of atoms of the active radio-element coating.
  • the deposition of the radio-element layer on the nickel substrate is carried out by evaporation under vacuum or by cathode sputtering of the oxide of the radio-element.
  • French patent 2,028,679 illustrates a process for manufacturing a radiation source, which consists in depositing on a support coated with enamel a radioactive material and then depositing on this material a layer waterproof metal oxide by hydrolyzing a chloride of this metal on the heated radioactive layer.
  • This method has the drawback of requiring an intermediate decontamination operation to remove the radioactive material which is not fixed on the support and of being unsuitable for industrial manufacture.
  • Also known from Swiss Patent 225,654 is a process for producing a radioactive source, according to which a radioactive substance is introduced into the pores of a porous layer produced on the surface of a support. metallic, which cannot lead to obtaining a source having satisfactory safety characteristics.
  • the process according to the invention overcomes the drawbacks of the processes mentioned above, in particular in that it makes it possible to carry out directly on the substrate the deposition of the active layer of radio-element from a nitric solution of this radio element.
  • the process which is the subject of the invention is characterized in that a metal substrate capable of resisting corrosion by nitric solutions is deposited on a substrate, chosen from the group comprising titanium, zirconium, a thin active layer d '' a radioelement by contacting a nitric solution of said radioelement with said substrate and dry evaporation of said solution, the substrate thus coated is subjected to a heat treatment so as to obtain a layer of an inactive coating consisting of a oxide of the metal constituting said substrate, then a refractory material is deposited by sputtering.
  • a layer of tantalum is also deposited on said refractory material.
  • the radioelement used as active layer of the considered source is generally a radioelement such as americium 241, plutonium 238 and curium 242 or 244.
  • a radioelement such as americium 241, plutonium 238 and curium 242 or 244.
  • the subsequent heat treatment causes the oxidation of the metal constituting the substrate, the metal oxide layer thus formed developing by oxidation of this metal which has diffused through the layers atoms constituting the active coating; therefore, the active radioelement layer is always at the metal-oxide interface.
  • a 4N radioactive element nitric solution is used.
  • a refractory material for example an enamel
  • a refractory material is deposited on the inactive coating layer.
  • the deposition of this layer of enamel preferably between 3 and 10 microns thick, is carried out by sputtering, the enamel being, for example a compound based on silicates.
  • the enamel instead of enamel, we can use a glass, calcium fluoride, titanium oxide or alumina.
  • the purpose of this refractory coating is to protect the inactive deposit in case of abrasion or accidental scratches, its role is also to perfect the source by the multilayer process.
  • a layer of tantalum is also deposited on the layer of refractory material; this deposition of a tantalum layer, preferably between 1 and 2 microns thick, is carried out by sputtering.
  • This tantalum layer allows the radioactive source to retain its safety character during use, can appropriately resist corrosion and undergo no degradation, either in air or in humidity. In addition, it can resist any rise in temperature: in fact, if the temperature remains below 600 ° C, the source does not undergo any destruction; moreover, if the temperature becomes higher than 600 ° C., the tantalum oxidizes.
  • the active layer of radio-element can be deposited from a nitric solution of this radio-element; B. 6472.3 MDT this allows a simpler, less expensive deposition technique and easier to automate than the implementation of vacuum evaporation or sputtering techniques involved in the prior process mentioned above.
  • the nitric solutions used are very stable and allow automation for mass production.
  • the resistance of titanium or zirconium to corrosion is very good and the radioactive sources obtained are of good quality.
  • the invention also relates to radioactive sources as obtained by the process considered. These sources are characterized in that they successively comprise a substrate made of a metal chosen from the group comprising titanium, zirconium, an active thin layer of a radio-element such as americium, plutonium, curium , a layer of an inactive coating. consisting of an oxide of said metal and a layer of a refractory material.
  • the sources further comprise a layer of tantalum deposited on the layer of refractory material.
  • FIGS. 1 to 3 This description refers to the appended FIGS. 1 to 3 in which curves have been shown which give for different sources, on the one hand, on the ordinate the number N of the particles leaving the sources and, on the other hand, on the abscissa the energy E in MeV of the particles.
  • a source of americium 241 is prepared in the following manner.
  • the energy of the particles is lower in the case of a source of the invention with coating of tantalum (curve C 5 ) compared to a source of the invention without coating of tantalum (curve C 3 ).
  • the radioactive sources according to the invention are more particularly intended for use in devices liable to undergo high temperature increases such as fire detectors, lightning conductors, or static electricity eliminators.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Physical Vapour Deposition (AREA)
  • Coating By Spraying Or Casting (AREA)

Abstract

1. Process for the manufacture of a radio-active source characterized in that a thin active layer of a radioelement is deposited on a titanium or zirconium substrate by contacting the substrate with a nitric solution of the said radioelement and evaporating said solution to dryness, the thus-coated substrate is subjected to a thermal treatment whereby to provide an inactive coating layer of an oxide of the metal forming the substrate, and then a refractory material is deposited by cathodic spraying.

Description

La présente invention a pour objet un procédé de fabrication d'une source radioactive et la source obtenue par ledit procédé.The present invention relates to a method for manufacturing a radioactive source and the source obtained by said method.

On connaît par le brevet français 2.279.206 un procédé de réalisation de sources de rayonnements ionisants selon lequel on dépose, sur un substrat en nickel, une couche active d'un radio-élément, puis on fait subir au substrat ainsi revêtu un traitement thermique de façon à provoquer la formation d'une couche inactive d'oxyde de nickel permettant la protection de la couche active de radio-élément, cet oxyde de nickel étant formé par oxydation du nickel qui constitue le substrat et qui a diffusé à travers les couches d'atomes du revêtement actif de radio- élément. Selon ce procédé, le dépôt de la couche de radio- élément sur le substrat en nickel est réalisé par évaporation sous vide ou par pulvérisation cathodique de l'oxyde du radioélément. En effet, on ne peut utiliser la technique de dépôt d'un radio-élément sur le substrat en nickel à partir d'une solution d'acide minéral du radio-élément étant donné que le nickel ne résisterait pas à la corrosion par cet acide minéral. On est donc obligé, selon le procédé considéré, de partir d'une solution alcoolique du radio- élément, dépourvue d'acide minéral, pour effectuer le dépôt de la couche active de radio-élément sur le substrat en nickel. Ceci pose un certain nombre de problèmes ; par exemple, lorsqu'on veut déposer une couche de plutonium sur le substrat en nickel, on se heurte à un certain nombre de difficultés du fait que le plutonium ayant une forte tendance à l'hydrolyse, les solutions alcooliques de ce composé sont peu stables et les précipités d'hydroxyde de plutonium y apparaissent très rapidement. D'autre part, il est dommage de ne pouvoir utiliser une solution acide de radioélément car l'utilisation de cette dernière permet d'obtenir une certaine migration dudit radioélément dans le substrat.French patent 2,279,206 discloses a process for producing sources of ionizing radiation according to which an active layer of a radio-element is deposited on a nickel substrate, and then the substrate thus coated is subjected to a heat treatment. so as to cause the formation of an inactive layer of nickel oxide allowing the protection of the active layer of radio-element, this nickel oxide being formed by oxidation of nickel which constitutes the substrate and which has diffused through the layers of atoms of the active radio-element coating. According to this process, the deposition of the radio-element layer on the nickel substrate is carried out by evaporation under vacuum or by cathode sputtering of the oxide of the radio-element. In fact, the technique of depositing a radio element on the nickel substrate from a mineral acid solution of the radio element cannot be used since nickel would not resist corrosion by this acid. mineral. It is therefore necessary, according to the process considered, to start from an alcoholic solution of the radio-element, devoid of mineral acid, in order to deposit the active layer of radio-element on the nickel substrate. This poses a number of problems; for example, when it is desired to deposit a layer of plutonium on the nickel substrate, one encounters a certain number of difficulties because plutonium having a strong tendency to hydrolysis, the alcoholic solutions of this compound are not very stable and plutonium hydroxide precipitates appear there very quickly. On the other hand, it is a pity not being able to use an acidic solution of radioelement because the use of the latter makes it possible to obtain a certain migration of said radioelement in the substrate.

Le brevet français 2.028.679 illustre un procédé de fabrication d'une source de rayonnements, qui consiste à déposer sur un support revêtu d'émail une matière-radioactive et à déposer ensuite sur cette matière une couche étanche d'oxyde métallique en hydrolysant un chlorure de ce métal sur la couche radioactive chauffée.French patent 2,028,679 illustrates a process for manufacturing a radiation source, which consists in depositing on a support coated with enamel a radioactive material and then depositing on this material a layer waterproof metal oxide by hydrolyzing a chloride of this metal on the heated radioactive layer.

Ce procédé présente l'inconvénient de nécessiter une opération de décontamination intermédiaire pour éliminer la matière radioactive non fixée sur le support et d'être peu adapté à une fabrication industrielle.This method has the drawback of requiring an intermediate decontamination operation to remove the radioactive material which is not fixed on the support and of being unsuitable for industrial manufacture.

On connaît encore par le brevet suisse 225.654 un procédé de réalisation d'une source radioactive., selon lequel on introduit une substance radioactive dans les pores d'une couche poreuse réalisée sur la surface d'un support. métallique, ce qui ne peut conduire à l'obtention d'une source présentant des caractéristiques de sécurité satisfaisantes .Also known from Swiss Patent 225,654 is a process for producing a radioactive source, according to which a radioactive substance is introduced into the pores of a porous layer produced on the surface of a support. metallic, which cannot lead to obtaining a source having satisfactory safety characteristics.

Le procédé conforme à l'invention pallie les inconvénients des procédés rappelés ci-dessus, notamment en ce qu'il permet d'effectuer directement sur le substrat le dépôt de la couche active de radio-élément à partir d'une solution nitrique de ce radio-élément.The process according to the invention overcomes the drawbacks of the processes mentioned above, in particular in that it makes it possible to carry out directly on the substrate the deposition of the active layer of radio-element from a nitric solution of this radio element.

Le procédé objet de l'invention, se caractérise en ce que l'on dépose sur un substrat en un métal susceptible de résister à la corrosion par des solutions nitriques, choisi dans le groupe comprenant le titane, le zirconium, une couche mince active d'un radioélément par mise en contact d'une solution nitrique dudit radioélément avec ledit substrat et évaporation à sec de ladite solution, on fait subir au substrat ainsi revêtu un traitement thermique de façon à obtenir une couche d'un revêtement inactif constitué d'un oxyde du métal constituant ledit substrat, puis on dépose un matériau réfractaire par pulvérisation cathodique.The process which is the subject of the invention is characterized in that a metal substrate capable of resisting corrosion by nitric solutions is deposited on a substrate, chosen from the group comprising titanium, zirconium, a thin active layer d '' a radioelement by contacting a nitric solution of said radioelement with said substrate and dry evaporation of said solution, the substrate thus coated is subjected to a heat treatment so as to obtain a layer of an inactive coating consisting of a oxide of the metal constituting said substrate, then a refractory material is deposited by sputtering.

Selon une caractéristique de l'invention, on dépose en outre sur ledit matériau réfractaire une couche de tantale.According to a characteristic of the invention, a layer of tantalum is also deposited on said refractory material.

Le radioélément utilisé en tant que couche active de la source considérée est en général un radioélément tel que l'américium 241, le plutonium 238 et le curium 242 ou 244. Après évaporation à sec de la solution nitrique du radio- élément, le traitement thermique subséquent provoque l'oxydation du métal constituant le substrat, la couche d'oxyde du métal ainsi formée se développant par oxydation de ce métal qui a diffusé à travers les couches d'atomes constituant le revêtement actif ; de ce fait, la couche active de radioélément se trouve toujours à l'interface métal-oxyde. De préférence, on utilise une solution nitrique de radio-élément 4N.The radioelement used as active layer of the considered source is generally a radioelement such as americium 241, plutonium 238 and curium 242 or 244. After dry evaporation of the nitric solution of the radio-element, the subsequent heat treatment causes the oxidation of the metal constituting the substrate, the metal oxide layer thus formed developing by oxidation of this metal which has diffused through the layers atoms constituting the active coating; therefore, the active radioelement layer is always at the metal-oxide interface. Preferably, a 4N radioactive element nitric solution is used.

Selon le procédé de l'invention, on dépose sur la couche de revêtement inactif un matériau réfractaire, par exemple un émail. Le dépôt de cette couche d'émail, d'une épaisseur de préférence comprise entre 3 et 10 microns, s'effectue par pulvérisation cathodique, l'émail étant, par exemple un composé à base de silicates. A la place de l'émail, on peut utiliser un verre, le fluorure de calcium, l'oxyde de titane où l'alumine. Le but de ce revêtement réfractaire est de protéger le dépôt inactif en cas d'abrasion ou d'éraflures accidentelles, son rôle est aussi de parfaire la source par le procédé multicouche.According to the method of the invention, a refractory material, for example an enamel, is deposited on the inactive coating layer. The deposition of this layer of enamel, preferably between 3 and 10 microns thick, is carried out by sputtering, the enamel being, for example a compound based on silicates. Instead of enamel, we can use a glass, calcium fluoride, titanium oxide or alumina. The purpose of this refractory coating is to protect the inactive deposit in case of abrasion or accidental scratches, its role is also to perfect the source by the multilayer process.

Selon un mode de réalisation du procédé de l'invention, on dépose en outre sur la couche du matériau réfractaire une couche de tantale ; ce dépôt d'une couche de tantale, d'une épaisseur de préférence comprise entre 1 et 2 microns, s'effectue par pulvérisation cathodique. La présence de cette couche de tantale permet que la source radioactive conserve son caractère de sécurité en cours d'utilisation, puisse résister de façon appropriée à la corrosion et ne subir aucune dégradation, ni à l'air, ni à l'humidité. De plus, elle peut résister à toute élévation de température : en effet, si la température demeure inférieure à 600°C, la source ne subit aucune destruction ; par ailleurs, si la température devient supérieure à 600°C, le tantale s'oxyde.According to one embodiment of the method of the invention, a layer of tantalum is also deposited on the layer of refractory material; this deposition of a tantalum layer, preferably between 1 and 2 microns thick, is carried out by sputtering. The presence of this tantalum layer allows the radioactive source to retain its safety character during use, can appropriately resist corrosion and undergo no degradation, either in air or in humidity. In addition, it can resist any rise in temperature: in fact, if the temperature remains below 600 ° C, the source does not undergo any destruction; moreover, if the temperature becomes higher than 600 ° C., the tantalum oxidizes.

Ainsi, grâce au procédé conforme à l'invention, on peut effectuer le dépôt de la couche active de radio-élément à partir d'une solution nitrique de ce radio-élément ; B. 6472.3 MDT
ceci permet une technique de dépôt plus simple, moins onéreuse, et plus facile à automatiser que la mise en oeuvre des techniques d'évaporation sous vide ou de pulvérisation cathodique intervenant dans le procédé antérieur rappelé ci-dessus. Les solutions nitriques utilisées sont très stables et permettent l'automatisation pour la réalisation de grande série. La résistance du titane ou du zirconium à la corrosion est très bonne et les sources radioactives obtenues sont de bonne qualité.Thus, thanks to the method according to the invention, the active layer of radio-element can be deposited from a nitric solution of this radio-element; B. 6472.3 MDT
this allows a simpler, less expensive deposition technique and easier to automate than the implementation of vacuum evaporation or sputtering techniques involved in the prior process mentioned above. The nitric solutions used are very stable and allow automation for mass production. The resistance of titanium or zirconium to corrosion is very good and the radioactive sources obtained are of good quality.

L'invention a également pour objet les sources radioactives telles qu'obtenues par le procédé considéré. Ces sources se caractérisent en ce qu'elles comportent successivement un substrat constitué d'un métal choisi dans le groupe comprenant le titane, le zirconium, une couche mince active d'un radio-élément tel que l'américium, le plutonium, le curium, une couche d'un revêtement inactif. constitué par un oxyde dudit métal et une couche d'un matériau réfractaire.The invention also relates to radioactive sources as obtained by the process considered. These sources are characterized in that they successively comprise a substrate made of a metal chosen from the group comprising titanium, zirconium, an active thin layer of a radio-element such as americium, plutonium, curium , a layer of an inactive coating. consisting of an oxide of said metal and a layer of a refractory material.

Selon un mode de réalisation, les sources comportent en outre une couche de tantale déposée sur la couche du matériau réfractaire.According to one embodiment, the sources further comprise a layer of tantalum deposited on the layer of refractory material.

La description qui suit se rapporte à un exemple de fabrication d'une source radioactive selon l'invention, cet exemple étant donné à titre illustratif et non limitatif.The description which follows relates to an example of manufacture of a radioactive source according to the invention, this example being given by way of nonlimiting illustration.

Cette description se réfère aux figures 1 à 3 annexées sur lesquelles on a représenté des courbes qui donnent pour différentes sources, d'une part, en ordonnée le nombre N des particules sortant des sources et, d'autre part, en abscisse l'énergie E en MeV des particules.This description refers to the appended FIGS. 1 to 3 in which curves have been shown which give for different sources, on the one hand, on the ordinate the number N of the particles leaving the sources and, on the other hand, on the abscissa the energy E in MeV of the particles.

Selon l'invention, on prépare une source d'américium 241 de la façon suivante.According to the invention, a source of americium 241 is prepared in the following manner.

On dépose sur un support en titane d'une épaisseur de 2mm et d'un diamètre de 10 mm, 10 pl d'une solution d'acide nitrique 4N contenant 0,1 g d'américium 241 par litre. Après évaporation de la solution par chauffage à 80°C, le support est porté à 700°C pendant 10 mn afin de provoquer l'oxydation superficielle du support et l'apparition d'une couche d'oxyde de titane au-dessus du dépôt d'américium 241. Le support est ensuite introduit dans une enceinte à vide équipée d'un dispositif de pulvérisation cathodique qui est un système diode fonctionnant en radiofréquence. Après obtention d'un vide de 10-4 torr, une pression d'argon d'environ 10-2 torr est introduite dans la cloche à vide et la pulvérisation cathodique du verre est mise en route pendant 30 mn environ, l'épaisseur du dépôt est de 3 p. En dernier lieu, on procède au dépôt d'un film de tantale de 2 p d'épaisseur par pulvérisation cathodique,10 μl of a 4N nitric acid solution containing 0.1 g of americium 241 per liter is deposited on a titanium support with a thickness of 2 mm and a diameter of 10 mm. After evaporation of the solution by heating to 80 ° C, the support is brought to 700 ° C. for 10 min in order to cause the surface oxidation of the support and the appearance of a layer of titanium oxide above the deposit of americium 241. The support is then introduced into an enclosure vacuum equipped with a sputtering device which is a diode system operating at radio frequency. After obtaining a vacuum of 10-4 torr, an argon pressure of approximately 10 -2 torr is introduced into the vacuum bell and the cathode sputtering of the glass is started for approximately 30 min, the thickness of the deposit is 3%. Finally, a 2 p thick tantalum film is deposited by sputtering,

On a représenté sur la figure 1 :

  • - une courbe C1, donnant, pour une source qui comporte successivement sur un substrat en titane, une couche d'américium, une couche d'oxyde de titane et une couche de tantale, l'énergie E en MeV des particules en fonction du nombre N des particules sortant de la source,
  • - une courbe C2 donnant, pour une source "nue" formée simplement d'un dépôt d'américium sur un substrat de titane, l'énergie E en MeV des particules en fonction du nombre N des particules sortant de cette source.
FIG. 1 shows:
  • a curve C 1 , giving, for a source which successively comprises on a titanium substrate, a layer of americium, a layer of titanium oxide and a layer of tantalum, the energy E in MeV of the particles as a function of number N of particles leaving the source,
  • - A curve C 2 giving, for a "naked" source formed simply of a deposit of americium on a titanium substrate, the energy E in MeV of the particles as a function of the number N of the particles leaving this source.

On a représenté sur la figure 2 :

  • - une courbe C3 donnant, pour une source conforme à l'invention sans revêtement de tantale, l'énergie E en MeV des particules en fonction du nombre N des particules sortant de la source,
  • - une courbe C4 qui est celle obtenue pour une source "nue" formée simplement d'un dépôt d'américium sur un support de titane.
FIG. 2 shows:
  • a curve C 3 giving, for a source according to the invention without coating of tantalum, the energy E in MeV of the particles as a function of the number N of the particles leaving the source,
  • - A curve C 4 which is that obtained for a "naked" source formed simply from a deposit of americium on a titanium support.

On a représenté sur la figure 3 :

  • - une courbe Cs donnant pour la source obtenue selon l'exemple décrit ci-dessus, c'est-à-dire une source conforme à l'invention avec revêtement de tantale, l'énergie E en MeV des particules en fonction du nombre N des particules sortant de la source,
  • - une courbe C6 qui est celle obtenue pour la source "nue".
FIG. 3 shows:
  • a curve C s giving for the source obtained according to the example described above, that is to say a source according to the invention with tantalum coating, the energy E in MeV of the particles as a function of the number N of particles leaving the source,
  • - a curve C 6 which is that obtained for the "naked" source.

On voit que l'énergie E des particules sortant des sources correspondant aux courbes C1, C3 et Ce est plus faible que pour une source "nue" formée simplement d'un dépôt du même radio-élément sur un substrat.It can be seen that the energy E of the particles leaving the sources corresponding to the curves C 1 , C 3 and Ce is lower than for a "naked" source formed simply by a deposit of the same radio-element on a substrate.

On peut noter également que l'énergie des particules est plus faible dans le cas d'une source de l'invention avec revêtement de tantale (courbe C5) par rapport à une source de l'invention sans revêtement de tantale (courbe C3).It can also be noted that the energy of the particles is lower in the case of a source of the invention with coating of tantalum (curve C 5 ) compared to a source of the invention without coating of tantalum (curve C 3 ).

Les sources radioactives conformes à l'invention sont plus particulièrement destinées à être utilisées dans des appareils susceptibles de subir de fortes élévations de températures tels que des détecteurs d'incendies, des paratonnerres, ou des éliminateurs d'électricité statique.The radioactive sources according to the invention are more particularly intended for use in devices liable to undergo high temperature increases such as fire detectors, lightning conductors, or static electricity eliminators.

Claims (7)

1. Procédé de fabrication d'une source radioactive, caractérisé en ce que l'on dépose sur un substrat en titane ou en zirconium, une couche mince active d'un radio- élément par mise en contact d'une solution nitrique dudit radio-élément avec ledit substrat et évaporation à sec de ladite solution, on fait subir au substrat ainsi revêtu un traitement thermique de façon à obtenir une couche d'un revêtement inactif constitué d'un oxyde du métal constituant ledit substrat, puis on dépose un matériau réfractaire par pulvérisation cathodique,1. A method of manufacturing a radioactive source, characterized in that a thin active layer of a radio-element is deposited on a titanium or zirconium substrate by contacting a nitric solution of said radio- element with said substrate and dry evaporation of said solution, the substrate thus coated is subjected to a heat treatment so as to obtain a layer of an inactive coating consisting of an oxide of the metal constituting said substrate, then a refractory material is deposited by sputtering, 2. Procédé selon la revendication 1, caractérisé en ce que l'on dépose en outre sur ledit matériau réfractaire une couche de tantale.2. Method according to claim 1, characterized in that a layer of tantalum is also deposited on said refractory material. 3. Procédé selon les revendications 1 et 2, caractérisé en ce que le matériau réfractaire est choisi dans le groupe constitué par un émail, un verre, le fluorure de calcium, l'oxyde de titane, l'alumine.3. Method according to claims 1 and 2, characterized in that the refractory material is chosen from the group consisting of an enamel, a glass, calcium fluoride, titanium oxide, alumina. 4. Procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce que la solution nitrique du radio-élément est constituée par une solution nitrique d'un radio-élément choisi dans le groupe comprenant le plutonium, l'américium, le curium.4. Method according to any one of claims 1 to 3, characterized in that the nitric solution of the radio-element consists of a nitric solution of a radio-element chosen from the group comprising plutonium, americium, curium. 5. Procédé selon la revendication 4, caractérisé en ce que la solution nitrique du radio-élément est une solution d'acide nitrique 4N.5. Method according to claim 4, characterized in that the nitric solution of the radio-element is a solution of 4N nitric acid. 6. Source radioactive, caractérisée en ce qu'elle comporte successivement un substrat constitué d'un métal choisi dans le groupe comprenant le titane, le zirconium, une couche mince active d'un radio-élément tel que l'américium, le plutonium, le curium, une couche d'un revêtement inactif constitué par un oxyde dudit métal, et enfin une couche d'un matériau réfractaire.6. Radioactive source, characterized in that it successively comprises a substrate made of a metal chosen from the group comprising titanium, zirconium, a thin active layer of a radio-element such as americium, plutonium, curium, a layer of an inactive coating consisting of an oxide of said metal, and finally a layer of a refractory material. 7. Source selon la revendication 6, caractérisée en ce qu'elle comporte en outre une couche de tantale déposée sur la couche du revêtement réfractaire.7. Source according to claim 6, characterized in that it further comprises a layer of tantalum deposited on the layer of the refractory lining.
EP19800400238 1979-03-02 1980-02-19 Process for manufacturing a radioactive source and radioactive source thus obtained Expired EP0015807B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7905498A FR2450498A1 (en) 1979-03-02 1979-03-02 METHOD FOR MANUFACTURING A RADIOACTIVE SOURCE AND SOURCE OBTAINED BY SAID METHOD
FR7905498 1979-03-02

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EP0015807A1 true EP0015807A1 (en) 1980-09-17
EP0015807B1 EP0015807B1 (en) 1983-04-13

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EP19800400238 Expired EP0015807B1 (en) 1979-03-02 1980-02-19 Process for manufacturing a radioactive source and radioactive source thus obtained

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EP (1) EP0015807B1 (en)
JP (1) JPS55119100A (en)
DE (1) DE3062662D1 (en)
FR (1) FR2450498A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0980077A1 (en) * 1998-08-10 2000-02-16 Centro De Investigaciones Energeticas Medioambientales Y Tecnologicas (C.I.E.M.A.T.) Procedure for the incorporation of hazardous or costly onto aluminium supports with very low thickness of anodising
WO2006004075A2 (en) * 2004-06-30 2006-01-12 Noriyoshi Tsuyuzaki Random pulse generation source, and semiconductor device, method and program for generating random number and/or probability using the source

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH225654A (en) * 1940-12-19 1943-02-15 Robert Dr Haefeli Radioactive object.
FR2028679A1 (en) * 1969-01-21 1970-10-16 Drabkina Lidiya Radioactive source for eliminating static charges
FR2279206A1 (en) * 1973-12-17 1976-02-13 Commissariat Energie Atomique PROCESS FOR MANUFACTURING SOURCES OF Sealed IONIZING RADIATION AND SOURCES OBTAINED BY THIS PROCESS

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH225654A (en) * 1940-12-19 1943-02-15 Robert Dr Haefeli Radioactive object.
FR2028679A1 (en) * 1969-01-21 1970-10-16 Drabkina Lidiya Radioactive source for eliminating static charges
FR2279206A1 (en) * 1973-12-17 1976-02-13 Commissariat Energie Atomique PROCESS FOR MANUFACTURING SOURCES OF Sealed IONIZING RADIATION AND SOURCES OBTAINED BY THIS PROCESS

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0980077A1 (en) * 1998-08-10 2000-02-16 Centro De Investigaciones Energeticas Medioambientales Y Tecnologicas (C.I.E.M.A.T.) Procedure for the incorporation of hazardous or costly onto aluminium supports with very low thickness of anodising
ES2152840A2 (en) * 1998-08-10 2001-02-01 Ct Investig Energeticas Ciemat Procedure for the incorporation of hazardous or costly onto aluminium supports with very low thickness of anodising
WO2006004075A2 (en) * 2004-06-30 2006-01-12 Noriyoshi Tsuyuzaki Random pulse generation source, and semiconductor device, method and program for generating random number and/or probability using the source
WO2006004075A3 (en) * 2004-06-30 2007-02-15 Noriyoshi Tsuyuzaki Random pulse generation source, and semiconductor device, method and program for generating random number and/or probability using the source
US8001168B2 (en) 2004-06-30 2011-08-16 Noriyoshi Tsuyuzaki Random pulse generation source, and semiconductor device, method and program for generating random number and/or probability using the source
EP1771946B1 (en) * 2004-06-30 2019-07-31 Noriyoshi Tsuyuzaki SEMICONDUCTOR DEVICE USING RANDOM PULSE GENERATION SOURCE FOR GENERATING RANDOM NUMBERs AND/OR PROBABILITY

Also Published As

Publication number Publication date
EP0015807B1 (en) 1983-04-13
FR2450498A1 (en) 1980-09-26
JPS55119100A (en) 1980-09-12
FR2450498B1 (en) 1982-03-19
DE3062662D1 (en) 1983-05-19

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