$Y_2O_3-CeO_2-ZrO_2$ 구조세라믹스의 제조 및 특성 : II. 소결체의 기계적 성질 및 열적 안정성 |
오혁상, 이윤복, 김영우1, 오기동, 박홍채 |
부산대학교 무기재료공학과 1포항산업과학연구원 |
Preparation and Characteristics of $Y_2O_3-CeO_2-ZrO_2$ Structural Ceramics : II. Mechanical Properties and Thermal Stability of Sintered Body |
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ABSTRACT |
ZrO2 powders stabilized with Y2O3 and CeO2 of various compositions were prepared by the coprecipitation of water-soluble ZrOCl2.8H2O, YCl3.6H2O and Ce(NO3)3.6H2O, and their compacts were pressurelessly sintered at 1400 and 150$0^{circ}C$ for 2hrs in air. 2mol% Y2O3-ZrO3 showed the most superior strength (1003MPa) and microhardness (12.6GPa), while 10 mol%CeO2-ZrO2 had the hightest toughness (13.3 MPa.m1/2) after sintering at 140$0^{circ}C$. The addition of Y2O3 into Y2O3-ZrO3 decreased mean grain size and increased strength and hardness but decrease toughness. On the other hand, the addition of CeO2 into Y2O3-ZrO2 enhanced the stability of tetragonal phase during low-temperature aging for a long time under hydrothermal atmosphere. |
Key words:
$Y_2O_3-CeO_2-ZrO_2$ powders, Strength, Microhardness, Toughness, Stability of tetragonal phase, Low-tem-perature aging, Hydrothermal atmosphere |
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