著者

水野 正雄 山田 豊章

出版者

The Ceramic Society of Japan

雑誌

Journal of the Ceramic Society of Japan (日本セラミックス協会学術論文誌) (ISSN:09145400)

巻号頁・発行日

vol.97, no.1131, pp.1334-1338, 1989-11-01 (Released:2010-08-06)

参考文献数

11

被引用文献数

1 3

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In the phase diagram study on the system Ga2O3-Sm2O3, the liquidus and eutectic temperatures were measured from the cooling curves of specimens by the specular reflection method with a heliostat type solar furnace. Quenched specimens from the melt were examined by X-ray diffractometry and chemical analysis. In the system, four compounds were found; garnet-type 3Sm2O3⋅5Ga2O3, perovskite-type SmGaO3, monoclinic 2Sm2O3⋅Ga2O3 and orthorhombic 3Sm2O3⋅Ga2O3. These compounds, showed no phase transition during repeated heating and cooling cycles. The compound 3Sm2O3⋅Ga2O3 was found to melt incongruently at 1755±20°C. The lattice parameter were determined to be a0=12.431Å for 3Sm2O3⋅5Ga2O3, a0=7.658Å, b0=10.856Å, c0=11.560Å, β=109.240 for 2Sm2O3⋅Ga2O3 and a0=11.400Å, b0=5.515Å, c0=9.070Å for 3Sm2O3⋅Ga2O3. The solidification points of 3Sm2O3⋅5Ga2O3 and 2Sm2O3⋅Ga2O3 were determined as 1680±20°C, and 1708±20°C, respectively. The phase diagram shows three eutectic points at 1555°C, 1640°C, and 1690°C with 22.5, 55, and 70mol% Sm2O3 composition, respectively. A high temperature phase diagram for Ga2O3-Sm2O3 system was proposed.