| abstract |
When the A1 content is 5 to 100 wtppm in terms of metal, and the Si content is 10 wtppm or less in terms of metal, a high density rare earth oxide raw material powder and a binder having a purity of 99.9% or more are used, and a molding density of 58% or more of the theoretical density ratio is obtained. Manufacture. After removing the binder by heat treatment, it is sintered for at least 0.5 hours at 1450 ° C. or more and 1700 ° C. or less in hydrogen, a rare gas or a mixed atmosphere thereof, or in a vacuum, and R 2 O 3 (R is Y, Dy, Ho, Er, Tm Permeable rare earth oxide sintered body represented by at least one element of the group consisting of (Yb) and (Lu). |