| 摘要 |
In a process for producing encapsulation tubes for nuclear reactor fuel rods, a zirconium-base alloy is extruded at a temperature below 680 DEG C and the extruded material (product) is cold-rolled. Between the individual cold rollings, intermediate annealings are carried out, at least one of which takes place at a temperature which exceeds 650 DEG C in the alpha -phase range. The final cold rolling is followed by a final annealing. According to the invention, the extruded product is cooled after every intermediate annealing exceeding 650 DEG C at a rate which is at least 5 DEG C/minute in the temperature range from the annealing temperature down to 650 DEG C before it is subjected to the next cold rolling. Annealings which take place after the final intermediate annealing at a temperature above 600 DEG C in the alpha -phase range are carried out at a temperature of not more than 600 DEG C. The encapsulation tubes produced in accordance with the invention have not only a high corrosion resistance but also good mechanical properties.
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