Abstract:
La présente invention est relative à un procédé de fabrication de tubes à base de zirconium formés de couches de composition différente. Le procédé consiste à préparer l'ébauche tubulaire destinée à former la couche externe du tube par roulage-soudage d'une feuille puis, à l'enfiler sur une autre ébauche tubulaire ou bloc d'âme de plus petit diamètre obtenu par perçage d'une billette et éventuellement revêtu intérieurement d'un placage, à souder les dites ébauches à leurs extrémités, enfin à soumettre l'ensemble à un traitement de mise en solution en phase bêta, suivi d'une trempe à l'eau et d'un filage. L'invention trouve son application dans la réalisation de tubes du type Duplex ou Triplex avec une mise au mille de zirconium améliorée tout en obtenant une bonne adhérence entre les couches dudit tube.
Abstract:
A zirconium based alloy plate of low irradiation growth, containing not more than 5 wt% Sn and/or not more than 5 wt% Nb, and the balance Zr of not less than 90 wt%. The alloy plate has such a texture that 〈0001〉 orientation (FR value) with respect to direction perpendicular to the surface of the plate ranges from 0.20 to 0.50. This alloy plate is effective in being used to form a fuel channel box (1). Also a fuel assembly using this channel box (1) is provided in which the crystal orientation of the zirconium alloy is made random by a heat treatment. Specifically, by the heat treatment, the Fr, Ft, and Fℓ values thereof are set to 0.25 to 0.50, 0.25 to 0.36, and 0.25 to 0.36, respectively.
Abstract:
. la torche (1) est du type à plasma d'arc non transféré ; . on dirige la buse (3) de ladite torche (1) vers un orifice (8), de façon que l'axe (4) de ladite buse et l'axe (6) dudit orifice soient au moins approximativement confondus ; et . on fait passer un flux (20) desdits déchets à travers ledit orifice (8), de façon qu'ils s'avancent vers ladite torche (1).
Abstract:
A zirconium-base alloy structural member, wherein at least one element selected from phosphours, vanadium, niobium, tantalum, arsenic, antimony, bismuth, sulfur, chromium, molybdenum, tungsten, selenium, tellurium and polonium is distributed on a surface of said member, particularly to a fuel covering tube or spacer for nuclear fuel assembly which is contained the element in a surface oxide layer. The final cold-rolled fuel covering tube is produced by the steps of annealing and coating with the element in the surface oxide layer. The spacer is produced by a step of coating with the element in the surface oxide layer. A process for preparation of a zirconium-base alloy structural member includes, in addition to subjecting a zirconium-base alloy to a final plastic working step, a step of coating its surface with the element. There can be obtained a zirconium-base alloy structural member exhibiting a high corrosion resistance and having a high ductility.
Abstract:
A method of coating a nuclear fuel with a burnable poison wherein the surface of the nuclear fuel is cleaned, and a burnable poison layer is then sputtered thereon. Preferably, a relatively low sputtering deposition rate is selected that would heat the nuclear fuel surface to less than 200°C and external heat is applied to heat the nuclear fuel surface to between 200°C and 600°C. To make the burnable poison layer less hygroscopic, an overcoat layer of a hydrophobic material is sputtered on the burnable poison layer.
Abstract:
Modifying standard Zircaloy alloy processing techniques by limiting the working and annealing temperatures utilized after conventional beta treatment results in Zircaloy alloy product having superior high temperature steam corrosion resistance.