二酸化ウラン燃料の活性化焼結, (III)

X線回折による格子定数の測定

抄録

Lattice-constant measurements by X-ray of the various UO₂ pellets, dealt with in the 1st and 2nd reports, lead to the results:
(1) The lattice constant of UO_2+x is a=(5.4701-0.05x)±0.0002Å, where x ranges 00.09.
(2) By being sintered at 1, 500°C for 2hr, UO₂ pellets containing excess oxygen are reduced to UO_2.00 in either dry or wet hydrogen, whereas in vacuo a minute amount of excess oxygen remains in the sintered pellets.
(3) In UO₂, TiO₂ (or lower oxide) is soluble, BeO practically insoluble, Al₂O₃ completely insoluble, and MgO slightly soluble. With the last additive, the formation of solid solution depends largely upon the amount of excess oxygen of UO₂.