| 摘要 |
PROBLEM TO BE SOLVED: To provide an oxide ceramic cold storage material having a large heat capacity in the cryogenic temperature range of <=10 K and free of breaking of granules during operation of a refrigerator. SOLUTION: Rare earth-aluminum oxide represented by the formula RXAl2- XO3 (where R is one or more rare earth elements selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu and 0.3<=X<=1.5) and containing 4-1,000 ppm by weight of alkaline earth elements such as Ca and Mg as a sintering aid is spherically granulated and the resulting granules are converted to a polycrystal sintered compact to obtain the rare earth-aluminum oxide ceramic cold storage material. In the granules of the cold storage material, a perovskite phase RA103 is the principal texture and alumina and rare earth oxides or a rare earth-aluminum garnet phase is uniformly dispersed in the perovskite phase texture. |
