EP0016252A1 - Procédé de fabrication d'un article absorbant les neutrons et articles absorbant les neutrons - Google Patents

Procédé de fabrication d'un article absorbant les neutrons et articles absorbant les neutrons Download PDF

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Publication number
EP0016252A1
EP0016252A1 EP79104502A EP79104502A EP0016252A1 EP 0016252 A1 EP0016252 A1 EP 0016252A1 EP 79104502 A EP79104502 A EP 79104502A EP 79104502 A EP79104502 A EP 79104502A EP 0016252 A1 EP0016252 A1 EP 0016252A1
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EP
European Patent Office
Prior art keywords
deposit
boron carbide
substrate
plasma
neutron absorbing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP79104502A
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German (de)
English (en)
Inventor
Peter T.B. Shaffer
Michael F. Gaffney
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.)
Unifrax 1 LLC
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Carborundum Co
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Filing date
Publication date
Application filed by Carborundum Co filed Critical Carborundum Co
Publication of EP0016252A1 publication Critical patent/EP0016252A1/fr
Ceased legal-status Critical Current

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    • GPHYSICS
    • G21NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21FPROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F1/00Shielding characterised by the composition of the materials
    • G21F1/02Selection of uniform shielding materials
    • G21F1/08Metals; Alloys; Cermets, i.e. sintered mixtures of ceramics and metals

Definitions

  • This invention relates to neutron absorbing articles, to methods for their manufacture and to their uses to prevent undesirable emissions of neutrons from sources thereof, such as spent nuclear fuel. More particularly, the invention is of a method for manufacturing such neutron absorbing articles wherein boron carbide and a metal or metal alloy matrix for the boron carbide are plasma sprayed onto a metal or metal alloy substrate, the article made and neutron absorbing uses thereof.
  • the B10 content of boron is known to be an especially useful neutron absorber.
  • Boron carbide has been employed for its neutron absorbing properties and articles containing boron carbide, in metallic and polymeric matrices,have been manufactured and have been successfully employed as neutron absorbers, sometimes in storage racks for spent nuclear fuels, which racks are usually located in aqueous storage pools.
  • phenolic resin is organic there is a possibliity that some decomposition thereof and loss of physical properties may be encountered after lengthy use, e.g., after 20 to 40 years.
  • a nuclear absorbing article it is sometimes advantageous for a nuclear absorbing article to be of better thermal conductivity than such articles based on phenolic resin (which has a comparatively low thermal conductivity). It is known that metals are much better conductors of heat than organic polymers and additionally, they are resistant to weakening due to radiation from nuclear materials.
  • a method of manufacturing a neutron absorbing article comprises plasma spraying boron carbide and a metallic substance selected from the group consisting of metals and metal alloys onto a substrate so that the boron carbide deposits on the substrate in a matrix of the metallic substance without oxidation of the boron thereof, so as to produce.
  • a neutron absorber that is stable when exposed to an aqueous pool medium in which racks of spent nuclear fuel are stored with a plurality of such neutron absorbing articles therein to absorb neutrons released by the spent fuel and thereby prevent undesirable neutron emissions therefrom.
  • the metal of the substrate prefferably be the same as the metal of the matrix and to be either aluminum, copper or stainless steel, the boron carbide and the matrix metal or alloy to be charged to the plasma gun in powder form, the plasma sprayed deposit to be 70 to 90% by volume of boron carbide and the thickness thereof to be from 3 to 6 mm. Also within the invention are the articles made and uses thereof in spent fuel storage racks and for similar neutron absorbing functions.
  • a suitable plasma spray gun usually of the Metco or Bay State type, capable of depositing from 2 to 10 kilograms per hour of aluminum (or equivalent weights of other metals), is designated by numeral 11.
  • the plasma spray gun is held above the work and at an angle to it, with the work passing in the direction of arrow 13 and the gun being moved reciprocatingly transversely with respect to the work.
  • a mixing chamber 21 is shown schematically, in which boron carbide particles and metal or metal alloy particles, preferably with the metal or metal alloy being the same as that of the substrate, are mixed together before addition through passageway 23 to the plasma stream.
  • Inlets and outlets for the plasma gas and electrical connections are not shown in the schematic view of the gun nor are holding and moving means illustrated because such are well known in the art.
  • the surface 20 of deposit 19 is not perfectly regular, due to the method of laying down the B 4 C - matrix plasma coating.
  • particles 21 of boron carbide are shown in greatly exaggerated form distributed evenly throughout metal matrix 23 of coating 19. Although not exactly illustrated in the figure the boron carbide particles preferably are from 70 to 90% by volume of the coating.
  • FIG. 3 the "rippled” or “weld-type” nature of the deposit is indicated, with the rippled surface being designated by numeral 25.
  • FIG. 4 such surface is shown ground flat as surface 27 of absorber 10'.
  • boron carbide particles at such surface are not shown but it will be understood that in grinding the surface down or otherwise smoothing it by removal of material at least some of the boron carbide particles will be exposed unless such surface is previously covered with a layer of the matrix metal, preferably by plasma spraying thereof, which is subsequently smoothed without cutting the carbide particles.
  • FIG. 5 another form of the invention is illustrated wherein the neutron absorbing coating is applied to two sides of a substrate material.
  • neutron absorber 29 includes substrate 31 coated on both major surfaces thereof with boron carbide- substrate material coatings 33 and 35, both of which are shown as smooth surfaced, although the surfaces thereof may also be like those of absorber 10, as in FIG'S. 1-3.
  • FIG. 6 illustrates a cylindrical or tubular substrate 37 having a neutron absorbing coating 39 on the exterior thereof, to form cylindrical neutron absorbing 41.
  • substrate 43 has a longitudinal cavity therein defined by side walls 45 and 47 and bottom wall 49.
  • such cavity is filled with a plasma sprayed coating 51 of boron carbide particles in matrix material to form neutron absorber 53 and in FIG. 9 neutron absorber 53' is shown wherein the extended surface 52 of the absorber of FIG. 8 has been machined away to produce a smooth surface 54.
  • spent fuel rack 55 includes sixteen assemblies 57, each of which is of essentially square cross-section and each of which includes an outer wall 59, an inner wall 61 and intermediate such walls and enclosed between them, tops 63 and bottoms, not illustrated, which seal off each of the assemblies about the contents, neutron absorbing plates 10'.
  • assemblies 57 Inside the assemblies of the rack arc stored the spent nuclear fuel rods, not specifically illustrated herein, which extend vertically through the assemblies and have access at the ends thereof to water or aqueous solution in a pool or suitable container, not illustrated, in which the racks are stored.
  • the assemblies of the rack are welded together and are supported on a bottom member 65,mounted on legs 67, which are adjustable in height to permit leveling of the rack.
  • neutron absorbing plates 10' which are of.uniform width, height and thickness, are slid into place between vertical rods 69, which are welded to the inner and outer walls 61 and 59, respectively.
  • the plasma spray gun may be any such gun of types known in the art which are capable of feeding a mixture of powders to an argon or other inert gas plasma and of spraying these at supersonic velocities onto substrate surfaces held near to them.
  • a Metco type 2MB plasma spray gun may be employed, using a B nozzle but in the present experiments a comparable gun made by Bay State Abrasives Co. is used.
  • the plasma gas flow and other conditions may be adjusted to obtain an effective plasma.
  • the gas flow is adjusted to within a range of 100 to 5,000 liters per hour, preferably 2,000 to 4,000 l./hr. at standard conditions, with the pressure being in the range of 1 to 7 kg./sq. cm., preferably 2 to 5 kg./sq.
  • the voltage is set to from 50 to 250, preferably 60 to 100 and the electric current flow is from 200 to 600, preferably 300 to 500 amperes.
  • the spray distance is 5 to 15 centimeters, preferably being from 7 to 12 cm.
  • the gun is inclined at an angle of 30 to 60°. It will normally be capable of depositing from 2 to 10 kilograms per hour of aluminum, preferably 5 to 10 kg./hr. thereof or equivalent amount of other metal, for example, from 4 to 20 kg./hr. of copper or of stainless steel.
  • the presence of the boron carbide affects the gun capacity about as if it were aluminum.
  • the substrate to which the plasma spray is applied is normally a metal or metal alloy but it is within the concept of this invention to apply such spray to other suitable substrates which possess the desirable chemical and physical properties to make them useful in neutron absorbing articles intended for employment in storage racks for spent nuclear fuel.
  • suitable substrates which possess the desirable chemical and physical properties to make them useful in neutron absorbing articles intended for employment in storage racks for spent nuclear fuel.
  • such substrate could be a phenol formaldehyde polymer or other suitable polymeric material or it might be a natural material, such as certain hardwoods or composites made from them-and a polymeric binder.
  • mineral and other inorganic materials dispersed in a suitable binder can be employed.
  • the use of organic substances is not preferred due to their possible deterioration over a period of use of the neutron absorber and similarly, the employment of mineral materials sacrifices thermal conductivity, which is an important advantage of metal or metal alloy-based substrates.
  • Various metals may be employed and without prejudice to the use of other metals, such as iron, steel, magnesium,and other alloys, such as brass and bronze, all of which arc satisfactorily conductive and which may be coated by the method of this invention, it is highly preferable to utilize aluminum, copper or stainless steel.
  • the substrate be of the same composition as the matrix material being applied to it (and the storage rack in which the absorber may be used).
  • the thicknesses of the .substrates and their shapes may vary but normally, as for a plate or tubular absorber to be coated with neutron absorbing material in a metal or alloy matrix, the thickness will be from 1 to 10 mm., preferably from 2 to 5 mm. It is usually desirable to employ comparatively thin substrates so as to keep the costs, thickness dimensions and weights of the finished articles as low as feasible. Thus, in addition to saving money there will be savings in structural supports for the storage racks or other apparatuses employed and it will be possible to have more racks in a given volume and to have them of greater neutron absorbing capabilities when the substrate thicknesses are kept low.
  • the substrates may be of other shapes too and may be made so that they can be bent to or assembled to desired shapes after manufacture.
  • the substrates may be of other shapes too and may be made so that they can be bent to or assembled to desired shapes after manufacture.
  • an uncoated substrate portion may be intermediate coated portions for bending along such uncoated surface to form other shapes of the final neutron absorbing article.
  • bending can be effected without adversely affecting the boron carbide-matrix deposit on the substrate.
  • the plasma spray may be deposited on items previously shaped, e.g., body armor, room walls, machine shields, equipment protective devices, live or spent nuclear fuel shipping casks, etc., which may be of thicknesses within the range previously given or greater than such thicknesses, as befits the particular application.
  • items previously shaped e.g., body armor, room walls, machine shields, equipment protective devices, live or spent nuclear fuel shipping casks, etc., which may be of thicknesses within the range previously given or greater than such thicknesses, as befits the particular application.
  • the boron carbide powder employed may be a commercial boron carbide which is low in boric oxide or other boron oxides, chloride and iron. Normally the chloride or other soluble salt content will be essentially nil, the iron content will be 3% or less, preferably 2% or less, more preferably 1% or less and most preferably will be less than 0.5%, with the B 2 O 3 (or other boron-oxygen compound, considered as a B 2 0 3 equivalent) content being no more than 2%, preferably less than 1%, more preferably less than 0.5% and most preferably less than 0.2%. The lower the iron and B 2 0 3 contents the better.
  • the percentages mentioned are those in the boron carbide (B 4 C) charged and in the deposit on the substrate (neglecting the metal or metal alloy matrix). Thus, the boric oxide content will be limited to the percentages mentioned, based on the boron carbide present. It-has been found that in plasma spraying with an inert gas and without the presence of combustible materials and oxygen present there may be a reduction in the boric oxide content of the boron carbide powder so that the final product is lower in B 2 0 3 than the powder charged. However, the important thing is that in the plasma spray operation no additional boric oxide is formed from the boron carbide, which may be the case with other high temperature and high velocity applications and methods, such as flame spraying.
  • the particle sizes of the boron carbide and matrix materials will usually be such that substantially all (over 90%, preferably over 95% and more preferably over 99%) passes through a No. 170 U.S. Sieve Series screen and at least 50% passes through a No. 200 screen.
  • the particle sizes are in the 20 to 200 micron range, more preferably in the 30 to 100 micron range.
  • Spherical or nearly spherical particles are preferred for th ⁇ ir ready miscibility and flowability.
  • the purities of the metals or metal alloys utilized are generally 99% or more, preferably at least 99.5% and more preferably at least 99.9%.
  • the boron carbide and metallic material particle sizes may be chosen to obtain the desired boron carbide particle size in the finished coating and to promote best bonding of the metallic material matrix to the boron carbide. In this respect it is considered that the finer the particle size the better for most applications providing that good flow and plasma melting of the particles are obtained (at least of the matrix).
  • Application of the plasma spray to the substrates may be by relative movement of the plasma gun and the substrate, either with the gun or the substrate moving or with both moving. Normally such application approximates that of paint spraying, with care being taken to evenly distribute the coating on the substrate.
  • Pluralities of coating layers may be employed and it is a feature of this invention that due to the excellent bonding of the plasma spray to the substrate and due to excellent bondings of subsequent sprays to previously deposited sprays, considerable thicknesses of the coating may be produced without bonding failure despite relatively minor proportions of matrix or binding material being utilized.
  • the thickness of boron carbide-matrix coating in which it is found that the boron carbide particles are very uniformly distributed, will normally be such that the B10 content thereof is that specified by the electric utility or other operator of the spent fuel storage pool or other facility or application in which neutron emission is to be controlled. Because such specification will normally be in the range of 0.01 to 0.1 g./sq. cm. of B 10 the thickness of the coating should usually be at least 0.5 mm. and preferably will be 3 to 6 mm., being 3 to 5 nun. after grinding or other surface removal of excess of coating to smooth such surface. Incidentally, such removal, in addition to being effectable by grinding, may also be accomplished by sonic and electrical discharge processes, among others.
  • both sides of the matrix are coated,one can further increase the neutron absorbing capability or can diminish the individual coating thicknesses while still having sufficient neutron absorbing power to satisfy specifications. It is within the present invention to effect coatings on both sides of an article simultaneously, in which case application rates can be doubled. It is also within the invention to apply the present coatings to both sides of cylindrical or tubular containers to make a modification of the coated cylinder of FIG. 6.
  • the substrate containing the cavity may contain cavities adjacent to both major surfaces thereof and coating material may be applied in both such cavities, after which it either may or may not be machined to final dimensions.
  • the walled cavities shown in FIG'S. 7-9 also help to stabilize the coating, protecting it from being dislodged or having its bonding to the substrate weakened by lateral blows.
  • transverse walls in the substrate may be utilized so that greater lengths, e.g., one meter, or more of deposit, are not made without a reinforcing substrate divider between them.
  • the walls of the cavity may be undercut to promote holding of the coating.
  • the deposit may be coated with matrix metal after grinding to be even with the substrate surface, and excess matrix may then be machined off to produce a smooth surface.
  • the present neutron absorbers in plate form, may be made as long as 2 to 7 meters, providing that the substrate is sufficiently strong so as to maintain its shape without undue bending, but preferably plate lengths will be from 0.5 to 2 meters, e.g., 1.5 meters.
  • the plates may be stacked one atop another and a plurality of plates may be employed within the walls of a storage rack assembly.
  • the present articles having very hard and comparatively smooth '(and. sometimes extremely smooth) surfaces, may be easily slid in and out of position without removing significant amounts of boron carbide particles, which can occur when the boron carbide particles are not as well covered by the matrix material as in the present products.
  • the useful lives of the present absorbers will exceed those of other nuclear absorbers presently in use because the coatings are so coherent and are so firmly held to the substrates and because the metals and alloys do not deteriorate during use due to radiation effects. Tests made on the articles of this invention indicate that they are superior to all other neutron absorbers presently in commercial use.
  • the manufacturing method lends itself to automation and to the speeding up of application techniques by the utilization of a plurality of plasma spray guns at one time coating a particular work.
  • the same plasma gun preferably equipped with adjustable feeding devices for the powders, can be used to spray various mixes of B 4 C and metallic material or the metal or alloy alone, without the need for changing guns or remounting the plasma gun.
  • Deposit thickness adjustments can be readily made, if desired. Initial special preparation of the powder charged to the plasma spray gun or supplying the charge as a rod is unnecessary and manufacturing costs are expected to be capable of being lowered so as to make them cheaper for the present products than costs for making other comparable neutron absorbers.
  • the neutron absorbing article In use in a fuel storage rack, as illustrated in FIG'S. 10 and 11, the neutron absorbing article is positioned with respect to a neutron emitting source so as to absorb neutrons emitted from it and prevent them from passing out of the storage area to areas where they might be damaging to personnel or equipment. They may be similarly employed in other neutron absorbing applications.
  • the absorbers When used in a spent fuel storage rack containing spent fuel (the racks of FIG'S. 10 and 11 may be considered as containing such fuel in the central portions thereof) the absorbers will be located so as to prevent release of neutrons past them.
  • the boron carbide-matrix deposition is interrupted, as in the articles of FIG'S. 7-9 and in similar products containing transverse walls about the illustrated cavities, the articles will be staggered or otherwise positioned so that the effective neutron absorbing coating will surround the spent nuclear fuel, preventing any escapes of neutrons through the substrate walls.
  • a flat strip of aluininum, about 8 cm. wide, 25 cm. long and 3 mm. thick is degreased, utilizing standard degreasing equipment, and is then roughened on. a major surface thereof by sand blasting, again using standard equipment. Areas to which the plasma sprayed coating is not to be applied are masked before sand blasting, using multiple layers of standard masking tape. Such tape may be removed or left on while plasma spraying onto the roughened surfaces.
  • a boron carbide powder containing less than 0.5% of boric oxide and of 260 mesh No. 260, U.S.
  • the products made are all useful as neutron absorbers except that those containing only 25% (even 50%) B 4 C are not nearly as satisfactory as the 75% product, which is decidedly superior. All the deposits made are firmly held to the substrate and are of high strength. However, they can be cracked off the substrate by excessive bending thereof although limited bending is possible without adversely affecting their properties. In this respect the 25% H 4 C product is less susceptible to such cracking.
  • Example 1 The experiment of Example 1 is repeated but instead of utilizing aluminum, copper particles and substrate are employed, with the weight percentages of the particles being increased so as to maintain the volume percentages the same as previously described. Also, the gun firing conditions, the argon feed, etc., are adjusted for best establishment of the plasma. Coatings of the thicknesses mentioned in Example 1 are applied and the products are examined and, like those of Example 1, appear to be strong, firmly adherent and uniform, suitable for use as neutron absorbers. However the 75% B 4 C product is most preferred, with the 50% product being considered to be next best as a neutron absorber.
  • Products like those of FIG'S. 5 and 6 are made by plasma spraying the compositions previously described in Examples 1-3 onto the indicated surfaces to make useful neutron absorbing articles.
  • the exteriors of square cross-section and rounded square cross-section tubes are so sprayed to produce a neutron absorbing tube which can be fitted about the neutron emitter in place of the inner walls of and absorber plates of the assemblies of FIG'S. 10 and 11.
  • the substrates utilized are modified, as shown in FIG'S. 7-9, and "75%" B 4 C deposits in matrices .of Al, Cu and stainless steel are applied, as in Examples 1-3.
  • the articles made are useful neutron absorbers
  • the products described in the foregoing examples are employed in absorbing neutrons generated by a neutron releasing material, such as spent nuclear fuel, in a fuel storage rack in a storage pool, which pool is filled with a normal aqueous storage pool medium containing boric acid.
  • the neutron absorbers operate effectively and when tested against the pool medium are found not to corrode objectionably.
  • the substrates and matrices employed in the neutron absorbing articles are of the same metals as those of the storage racks.
  • the coatings of the previous examples are applied to various other substrates, preformed or to be formed subsequently,and are applied interiorly, exteriorly, about curves, about angles and in such curves and angles, and the coatings made firmly adhere to the surfaces of the substrates, which are of the same materials as the coatings, and are useful as neutron absorbers.
  • the substrates are of different metals or alloys from the matrix of the coating, firm adherences are obtained and good products are made but there is some danger of galvanic corrosion, especially over long periods of time and if the absorber should be exposed to water or a humid atmosphere.
  • boron carbide such as silicon carbide
  • some of the boron carbide may be replaced with other neutron absorbers, e.g., boron nitride, and useful products result.
  • this invention is directed primarily to making a superior neutron absorber based on boron carbide.

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  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Coating By Spraying Or Casting (AREA)
EP79104502A 1979-02-21 1979-11-14 Procédé de fabrication d'un article absorbant les neutrons et articles absorbant les neutrons Ceased EP0016252A1 (fr)

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US1355579A 1979-02-21 1979-02-21
US13555 1979-02-21

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JP (1) JPS55113999A (fr)
BR (1) BR8000513A (fr)
ES (1) ES485589A1 (fr)
FI (1) FI793353A (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0055679A2 (fr) * 1980-12-31 1982-07-07 Framatome Boitier pour le stockage sous eau d'assemblages combustibles irradiés et procédé de réalisation d'un tel boitier
DE3344525A1 (de) * 1983-12-09 1985-06-20 Kernforschungsanlage Jülich GmbH, 5170 Jülich Verfahren zur lagerung abgebrannter brennelemente
FR2570001A1 (fr) * 1984-09-07 1986-03-14 Tech Milieu Ionisant Procede de depot d'un materiau constitue en majeure partie par un metal, un alliage, du bore et/ou une substance ceramique, utilisable pour la realisation de blindages ou d'ecrans biologiques
FR2608828A1 (fr) * 1986-12-17 1988-06-24 Commissariat Energie Atomique Procede de realisation d'un materiau composite, en particulier d'un materiau composite neutrophage
CH675699A5 (en) * 1988-06-21 1990-10-31 Alusuisse Lonza Holding A G Prodn. of boron contg. aluminium alloy - by spraying melt predetermined with current of support gas carrying boron particles substrate surface
WO1995030990A1 (fr) * 1994-05-09 1995-11-16 Siemens Aktiengesellschaft Recipient permettant d'absorber des radiations neutroniques
EP0849767A2 (fr) * 1996-12-19 1998-06-24 Applied Materials, Inc. Pièces et revêtements en carbure de bore dans un réacteur à plasma
US7295646B1 (en) 1999-09-27 2007-11-13 Metallveredlung Gmbh & Co. Kg Method for producing a coating for absorption of neutrons produced in nuclear reactions of radioactive materials
US8187720B2 (en) * 2005-11-14 2012-05-29 Lawrence Livermore National Security, Llc Corrosion resistant neutron absorbing coatings
CN102982856A (zh) * 2011-05-07 2013-03-20 Gip国际有限公司 用于核反应堆应用的中子吸收复合材料
US10580540B2 (en) 2014-08-13 2020-03-03 Curtiss-Wright Flow Control Corporation Neutron absorber member configured for insertion into a control rod guide tube of a spent fuel assembly

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2563652B1 (fr) * 1984-04-25 1986-07-25 Bignier Schmid Laurent Procede de fabrication d'une enveloppe a double paroi contenant un ecran absorbeur de neutrons pour le transport et le stockage d'une matiere radioactive

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2727996A (en) * 1952-08-11 1955-12-20 Iii Theodore Rockwell Thermal neutron shield and method for making same
FR1252868A (fr) * 1960-01-29 1961-02-03 Larderello écran protecteur contre les neutrons thermiques et son procédé de fabrication
GB1075655A (en) * 1963-06-21 1967-07-12 Norton Co Process for applying a refractory coating and articles comprising such a coating

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2727996A (en) * 1952-08-11 1955-12-20 Iii Theodore Rockwell Thermal neutron shield and method for making same
FR1252868A (fr) * 1960-01-29 1961-02-03 Larderello écran protecteur contre les neutrons thermiques et son procédé de fabrication
GB1075655A (en) * 1963-06-21 1967-07-12 Norton Co Process for applying a refractory coating and articles comprising such a coating

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0055679A2 (fr) * 1980-12-31 1982-07-07 Framatome Boitier pour le stockage sous eau d'assemblages combustibles irradiés et procédé de réalisation d'un tel boitier
WO1982002453A1 (fr) * 1980-12-31 1982-07-22 Framatome Sa Boitier pour le stockage sous eau d'assemblages combustibles irradies et procede de realisation d'un tel boitier.
EP0055679A3 (fr) * 1980-12-31 1982-09-01 Framatome Boitier pour le stockage sous eau d'assemblages combustibles irradiés et procédé de réalisation d'un tel boitier
DE3344525A1 (de) * 1983-12-09 1985-06-20 Kernforschungsanlage Jülich GmbH, 5170 Jülich Verfahren zur lagerung abgebrannter brennelemente
US4756871A (en) * 1983-12-09 1988-07-12 Kernforschungsanlage Julich Gmbh Method of storing spent nuclear fuel elements
FR2570001A1 (fr) * 1984-09-07 1986-03-14 Tech Milieu Ionisant Procede de depot d'un materiau constitue en majeure partie par un metal, un alliage, du bore et/ou une substance ceramique, utilisable pour la realisation de blindages ou d'ecrans biologiques
FR2608828A1 (fr) * 1986-12-17 1988-06-24 Commissariat Energie Atomique Procede de realisation d'un materiau composite, en particulier d'un materiau composite neutrophage
EP0275746A1 (fr) * 1986-12-17 1988-07-27 Commissariat A L'energie Atomique Procédé de réalisation d'un matériau composite, en particulier d'un matériau composite neutrophage
CH675699A5 (en) * 1988-06-21 1990-10-31 Alusuisse Lonza Holding A G Prodn. of boron contg. aluminium alloy - by spraying melt predetermined with current of support gas carrying boron particles substrate surface
WO1995030990A1 (fr) * 1994-05-09 1995-11-16 Siemens Aktiengesellschaft Recipient permettant d'absorber des radiations neutroniques
DE4416362C2 (de) * 1994-05-09 2002-09-26 Framatome Anp Gmbh Absorberteil
EP0849767A2 (fr) * 1996-12-19 1998-06-24 Applied Materials, Inc. Pièces et revêtements en carbure de bore dans un réacteur à plasma
EP0849767A3 (fr) * 1996-12-19 2001-03-21 Applied Materials, Inc. Pièces et revêtements en carbure de bore dans un réacteur à plasma
US6808747B1 (en) 1996-12-19 2004-10-26 Hong Shih Coating boron carbide on aluminum
US7295646B1 (en) 1999-09-27 2007-11-13 Metallveredlung Gmbh & Co. Kg Method for producing a coating for absorption of neutrons produced in nuclear reactions of radioactive materials
US8187720B2 (en) * 2005-11-14 2012-05-29 Lawrence Livermore National Security, Llc Corrosion resistant neutron absorbing coatings
US8580350B2 (en) * 2005-11-14 2013-11-12 Lawrence Livermore National Security, Llc Corrosion resistant neutron absorbing coatings
CN102982856A (zh) * 2011-05-07 2013-03-20 Gip国际有限公司 用于核反应堆应用的中子吸收复合材料
US10580540B2 (en) 2014-08-13 2020-03-03 Curtiss-Wright Flow Control Corporation Neutron absorber member configured for insertion into a control rod guide tube of a spent fuel assembly

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JPS55113999A (en) 1980-09-02
BR8000513A (pt) 1980-10-14
FI793353A (fi) 1980-08-22
ES485589A1 (es) 1980-09-01

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