caa a22 4500 388020407 CHVBK 20180307124922.0 cr unu---uuuuu 161130e199809 xx s 000 0 eng 10.1557/JMR.1998.0362 doi S0884291400045982 pii (NATIONALLICENCE)cambridge-10.1557/JMR.1998.0362 High-temperature Creep Resistance in Rare-earth-doped, Fine-grained Al2O3 [Elektronische Daten] High-temperature creep in undoped Al2O3 and La2O3- or Y2O3- or Lu2O3-doped Al2O3 with a grain size of about 1 µm is examined in uniaxial compression testing at temperatures between 1150 and 1350 °C. The high-temperature creep resistance in Al2O3 is highly improved by the rare-earth oxide doping in the level of 0.045 mol %, and the creep rate is suppressed in the order La2O3 <Y2O3 <Lu2O3. Rare-earth ions in each doped Al2O3 are found to segregate in Al2O3 grain boundaries without forming amorphous phase or second-phase particles. The activation energy for creep in undoped Al2O3 is estimated to be 410 kJ/mol, while it is about 800 kJ/mol in the three rare-earth oxide-doped Al2O3. The grain boundary diffusivity must be highly reduced by the segregation of the dopant cation in Al2O3 grain boundaries. Copyright © Materials Research Society 1998 Yoshida H. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan Ikuhara Y. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan Sakuma T. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan Journal of Materials Research Cambridge University Press 13/9(1998-09), 2597-2601 0884-2914 13:9<2597 1998 13 JMR https://doi.org/10.1557/JMR.1998.0362 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1557/JMR.1998.0362 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yoshida H. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan NATIONALLICENCE 700 1- Ikuhara Y. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan NATIONALLICENCE 700 1- Sakuma T. Ceramic Materials Laboratory, Department of Material Science, Faculty of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan NATIONALLICENCE 773 0- Journal of Materials Research Cambridge University Press 13/9(1998-09), 2597-2601 0884-2914 13:9<2597 1998 13 JMR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge