Compagnie Europeenne Du Zirconium Cezus

Claude Simonot

Pierre Barberis

The invention relates to a method of producing a flat zirconium alloy product with a Kearns factor (cross direction) of between 0.3 and 0.7. The inventive method consists in: producing an ingot containing Nb=0.5 to 3.5%, Sn=0 to 1.5%, Fe=0 to 0.5%, Cr+V=0 to 0.3%, S=0 to 100 ppm, O=0 to 2000 ppm, Si=0 to 150 ppm, the remainder being zirconium and impurities; shaping the aforementioned ingot; performing one or more hot rolling operations in order to obtain a flat product, whereby the last operation is performed at between(810&#x2212;20&#xd7;Nb %)&#xb0; C. and 1100&#xb0; C. and is not followed by any quenching from phase &#x3b1;+&#x3b2; or &#x3b2;; optionally performing an annealing operation at a maximum of 800&#xb0; C.; and performing one or more cold rolling and annealing operations, said annealing operations being performed at a maximum of 800&#xb0; C. The invention also relates to the flat zirconium alloy product thus obtained. The invention further relates to a support grid for fuel rods in a nuclear plant reactor, which is obtained by shaping the flat product.

Method of producing a flat zirconium alloy product, flat product thus obtained and a nuclear plant reactor grid which is made from said flat product

A method of fabricating a zirconium alloy flat product, the method being characterized by: preparing or casting a zirconium alloy ingot containing at least 95% by weight of zirconium, and including the usual impurities and alloying elements; shaping said ingot in order to obtain a flat product; subjecting said flat product to a &#x3b2; quenching operation under conditions that are determined to obtain within the flat product an acicular structure at the end of said &#x3b2; quenching; subjecting said flat product, after the &#x3b2; quenching, to a rolling operation performed in a single rolling sequence without intermediate annealing, said rolling being performed at a temperature lying in the range ambient to 200&#xb0; C., and having a reduction ratio lying in the range 2% to 20%; and subjecting said rolled flat product to an annealing treatment in the a range or in the &#x3b1;+&#x3b2; range, performed in the temperature range 500&#xb0; C. to 800&#xb0; C. for 2 minutes to 10 hours. A zirconium alloy flat product as obtained by the method, and a fuel assembly element for a power station nuclear reactor obtained by shaping the product.

Method for making a flat zirconium alloy product, resulting flat product and fuel, assembly component for nuclear power plant reactor made from said flat product

Growing community of inventors

L'Aigle, France

Claude Simonot