Articles, such as tubing, which have excellent corrosion resistance to steam at elevated temperatures and to hydriding, are produced from zirconium alloys containing 0.5 to 2.0 percent niobium, up to 1.5 percent tin, and up to 0.25 percent of a third alloying element such as iron, chromium, molybdenum, vanadium, copper, nickel and tungsten. The articles are formed by beta-treating the alloy, initially deforming the same at a temperature below 650° C. and further deforming the same through cold working stages also below 650° C., annealing the material between the cold working stages at a temperature between 500°-650° C., and final annealing the same at a temperature below 650° C. to provide articles having a microstructure of fine precipitates of less than about 800 Å, homogeneously dispersed throughout the zirconium.

Process for fabricating a zirconium-niobium alloy and articles resulting therefrom

The creep strength of a tube formed from a "Zircaloy" material is improved by prefacing the final cold working step of the manufacturing procedure by heating the material to the beta -range and then cooling to room temperature.

Method of making tubes and similar products of a zirconium alloy

The present invention provides a cladding having an outer circumferential substrate, a zirconium barrier layer metallurgically bonded to the inside surface of the substrate and an inner circumferential liner metallurgically bonded to the zirconium barrier The inner circumferential liner is more ductile than conventional Zircaloy The low ductility of the inner circumferential liner is obtained by using a zirconium alloy containing a low tin content (eg less than 12% by weight) and/or a low oxygen content (eg less than 1000 ppm) The inner circumferential liner is less than about 25 micrometers thick

Method for making fuel cladding having zirconium barrier layers and inner liners

A fuel assembly, where crystallographic orientations of a channel box are brought into a random distribution; and cladding tubes, spacers and a channel box are made from highly corrosion-resistant, Fe--Ni, zirconium-based alloy, hardened in the (α+β) phase or β-phase temperature region, has an average discharge burnup level of 50 to 550 GWd/t.

Fuel assembly, components thereof and method of manufacture

A cladding tube having a cross-section and including (1) a zirconium alloy outer circumferential substrate having an inner surface and having one or more alloying elements, (2) a zirconium barrier layer bonded to the inner surface of the outer circumferential substrate and being alloyed with the one or more alloying elements, and (3) a zirconium alloy inner circumferential liner bonded to the inner surface of the zirconium barrier layer. The barrier layer will have a concentration profile including a diffusion layer extending from the barrier layer's inner surface (facing nuclear fuel) to the barrier layer's interior (between the barrier layer's inner and outer surfaces). At the interior edge of the diffusion layer, there will be substantially no alloying elements. At the outer edge of the diffusion layer (the barrier layer's inner surface), the maximum concentration of alloying elements will occur.

Nuclear fuel cladding having an alloyed zirconium barrier layer

A PROCESS IS DESCRIBED IN WHICH ZIRCONIUM AND ITS ALLOYS ARE SUBJECTED TO A BETA PHASE HEAT TREATMENT AND DURING SAID HEAT TREATMENT A SURFACE ACTIVE AGENT IS ADMITTED TO THE HEAT TREATING ENVIRONMENT. THEREAFTER, THE METAL OR ALLOY IS COOLED TO A TEMPERATURE BELOW THE ALLOTROPIC TRANSFORMATION TEMPERATURE. THE METAL OR ALLOY THUS TREATED IS CHARACTERIZED BY A PREFERRED ORENTATION WHICH INCLUDES A HIGH VOLUME PROPORTION OF THE GRAINS EXHIBITING THE BASAL PLANE (0002) ORIENTED TO WITHIN 15* OF THE SURFAE OF THE MATERIAL.

George W Wiener

Papers

Process for obtaining preferred orientation in zirconium and its alloy