PREPARATION OF THE BI2O3-BASED FLUORITE-TYPE SOLID-SOLUTIONS BY MECHANICAL ALLOYING

A mechanical alloying technique was applied to the mixtures of (Bi2O3) (0.75)(Y2O3)(0.25) and (Bi2O3)(0.80)(Nb2O5)(0.20) to synthesize solid solutions of the fluorite-type structure. Amorphization occurred for ( Bi2O3)(0.80)(Y2O3)(0.25) while the fluorite-type phase is directly obt ained for (Bi2O3)(0.80)(Nb2O5)(0.20) by ball milling for 120 h. The am orphous sample of (Bi2O3)(0.75)(Y2O3)(0.25) turned into the fluorite-t ype phase under the condition of 500 degrees C and 10 minutes annealin g, which was much more mild as compared to that of the conventional so lid state reaction.