Thermophysical properties of americium-containing barium plutonate

Am含有BaPuOの熱物性

田中 康介  ; 佐藤 勇; 廣沢 孝志  ; 黒崎 健*; 牟田 浩明*; 山中 伸介*

Tanaka, Kosuke; Sato, Isamu; Hirosawa, Takashi; Kurosaki, Ken*; Muta, Hiroaki*; Yamanaka, Shinsuke*

BaPuAm)Oを調製し、ペロブスカイト型結晶構造を確認するとともに、音速測定により弾性率及びデバイ温度を求めた。また、熱伝導率を評価し、マトリクスと比較してきわめて小さい値を示すことがわかった。熱伝導率とデバイ温度の関係から、Ba系ペロブスカイト化合物の熱伝導率は原子間結合力の大きさで説明できることを明らかにした。

Polycrystalline specimens of americium-containing barium plutonate have been prepared by mixing the appropriate amounts of (PuAm)O and BaCO powders followed by reacting and sintering at 1600 K under the flowing gas atmosphere of dry-air. The sintered specimens had a single phase of orthorhombic perovskite structure and were crack-free. The elastic moduli were determined from the longitudinal and shear sound velocities. The Debye temperature was also determined from the sound velocities and lattice parameter measurements. The thermal conductivity was calculated from the measured density at room temperature, literature values of heat capacity, and thermal diffusivity measured by laser flash method in vacuum. The thermal conductivity of americium-containing barium plutonate was roughly independent of the temperature and was almost the same magnitude as that of BaPuO and BaUO.