著者

久森 紀之 野末 章 木村 雄二

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.67, no.657, pp.844-851, 2001-05-25

被引用文献数

2

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High-temperature and high-pressure water corrosion behaviors of Y_2O_3 doped Zirconia (ZrO_2) were investigated in term of with the microstructural changes, residual strength characteristics and tetragonal to monoclinic phase transformation. Sintered ZrO_2 ceramics bodies with 2, 3, 4, 6 and 8 mol% Y_2O_3 doped ZrO_2 were made using a pressure less sintering method at 1 450℃, respectively. These ZrO_2 ceramics were corroded in high-temperature and high-pressure water condition such as 150℃〜300℃. Corrosion damage of the decrease Y_2O_3 dope ZrO_2 ceramics occurred preferentially on ZrO_2 particle after long-term immersion in high-temperature and high-pressure water environment. The tetragonal to monoclinic phase transformation occurred in decrease Y_2O_3 doped tetragonal ZrO_2 ceramics due to high-temperature and high-pressure water corrosion. For improvement of the corrosion characteristics (thermal stability) of the ZrO_2 ceramics, are important increasing the Y_2O_3 doped within a range in which no remarkable residual strength degradation is recognized. CeO_2 doped ZrO_2 ceramics were useful to improvement the thermal stability of Y_2O_3 doped ZrO_2 without loss of the fracture strength. CeO_2 doped ZrO_2 ceramics also have superior residual strength characteristics compared to Y-ZrO_2 ceramics. In addition design concepts used to obtain water-corrosion-resistant high strength and high toughness ZrO_2 ceramics were proposed.