Method for providing a diffusion barrier
AssigneeAB Asea-Atom
InventorGunnar Vesterlund
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Abstract
A method for providing a barrier against copper diffusion into a zirconium alloy tube which is lined with copper for the purpose of increasing the resistance of the tube to stress corrosion induced by fission products when the tube is used to fuel a nuclear reactor. The method involves the deposition of a copper lining on the zirconium alloy tube and the subsequent exposure of the lined tube to a substance such as steam, water, nickel oxide or carbon dioxide or another material which has the ability to oxidize the zirconium without oxidizing the copper. Thus, a zirconium oxide layer is developed between the zirconium alloy tube and the copper lining thereon.
Claims6
A method for manufacturing a diffusion resistant, copper clad, zirconium alloy tube comprising:
- furnishing a tube constructed of a zirconium alloy material;
- depositing a copper lining on at least the internal surfaces of said tube;
- and
- contacting at least the internal copper-lined surfaces of the tube with steam at a temperature in the range of 200 to 550.degree. C. until a barrier of zirconium oxide is formed between the copper lining and the zirconium-based alloy.
Dependencies are inferred from the claim text.