Thin flat zirconium alloy elements, especially for nuclear fuel rod spacer elements, are produced using long low temperature intermediate anneal or pre-anneal in multi-pass cold rolling operation

摘要

Thin flat zirconium alloy element production comprises long low temperature intermediate anneal or pre-anneal in a multi-pass cold rolling operation. Thin flat elements are made from a zirconium alloy, containing (wt.%): 0.8-1.3% niobium; 500-2000 ppm oxygen; 5-35 ppm sulfur; and optionally up to 0.25% iron + chromium + vanadium and up to 300 ppm tin, by beta quenching and hot rolling to produce a blank and cold rolling in three or more passes with intermediate anneals, one of the intermediate anneals or a heat treatment before the first cold rolling pass being carried out for greater than or equal to 2 hours at below 600 deg C and any heat treatments after this long heat treatment being carried out at below 620 deg C for not more than 15 minutes. An Independent claim is also included for a thin sheet of a nuclear fuel assembly spacer element formed by cutting and drawing a thin element made by the above process.