Solute and defect segregation at the space charge layers of Fe-doped fine-grained Al2O3:: Effect on the creep rate

被引：6

作者：

Bataille, A. ^{[1
]}

Addad, A. ^{[1
]}

Courtois, C. ^{[2
]}

Duhoo, T. ^{[1
]}

Crampon, J. ^{[1
]}

机构：

[1] Univ Sci & Technol Lille, CNRS, Lab Struct & Proprietes Etat Solide, UMR 8008, F-59655 Villeneuve Dascq, France

[2] Univ Valenciennes & Hainaut Cambresis, Lab Mat & Procedes, EA 4015, F-59600 Maubeuge, France

来源：

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY | 2008年 / 28卷 / 06期

关键词：

Al2O3; creep; defects; grain boundary; space charge;

D O I：

10.1016/j.jeurceramsoc.2007.09.054

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Compressive creep in air of vacuum hot-pressed undoped alumina and 0.5 at.% iron doped alumina materials was investigated. The dark green colour of doped alumina accounted for the presence of iron as Fe2+ species at first. Also, iron rich precipitates were observed and identified as FeAl2O4 spinel. During the tests, Fe2+ species underwent oxidation during creep. The space charge concept is developed to account for the data and the interaction between the space charge and the extrinsic defect species. The observed iron segregation is proposed in the subgrain boundary region. Iron spinel precipitates were observed interacting with grain boundaries. Oxidation of Fe2+ resulted in Fe3+, which segregated into the grain boundaries. This segregation produced creep resistance of alumina. (c) 2007 Elsevier Ltd. All rights reserved.

引用

页码：1129 / 1134

页数：6

共 39 条

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