Mechanical properties of calcium- and strontium-substituted lanthanum chromite

被引：57

作者：

Paulik, SW ^{[1
]}

Baskaran, S ^{[1
]}

Armstrong, TR ^{[1
]}

机构：

[1] Pacific NW Lab, Richland, WA 99352 USA

来源：

JOURNAL OF MATERIALS SCIENCE | 1998年 / 33卷 / 09期

关键词：

D O I：

10.1023/A:1004359925766

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Mechanical properties of acceptor (calcium and strontium)-substituted lanthanum chromites are reported as a function of composition, temperature and environment. The strength dependence on temperature for these perovskite conductors was found to depend on the acceptor type, with the calcium-substituted chromites showing a significant reduction in strength with increasing temperature, while the strength of strontium-substituted chromites was essentially invariant with temperature. The decrease in strength observed upon annealing in highly reducing environments was correlated to changes in lattice structure, stoichiometry and fracture morphology. A significant observation was the decrease in the cohesive strength of the grains relative to grain boundaries, beyond a critical oxygen vacancy concentration in the chromites. The structural changes in the chromite lattice upon reduction also resulted in decreased fracture toughness. (C) 1998 Chapman & Hall.

引用

页码：2397 / 2404

页数：8

共 29 条

[1]

Anderson O, 1973, Elastic constants and their measurements

[2] A CRITICAL-EVALUATION OF INDENTATION TECHNIQUES FOR MEASURING FRACTURE-TOUGHNESS .1. DIRECT CRACK MEASUREMENTS [J].