Program to study the effects of neutron irradiation upon niobium base alloys

heat-treatment specifications for the EBWR fuel plates. In later studies on specimens cut from plates it was learned that the alloy could be adequately stabilized against irradiation growth and also made corrosion- resistent by first reducing the plate 12% in thickness by cold rolling followed by a 24-hr isothermal transformation from the gamma phase at 665 deg C, and finally quenching from 800 deg C. Irradiation growth rates of plate specimens were effectively reduced by the presence of metallurgically bonded Zircaloy-2 cladding. Flat-rolled material under irradiation generally increased in length and width and decreased in thickness. (auth)