Effect of local oxygen activity on Ni-BaTiO3 interfacial reactions

被引：63

作者：

Yang, G. Y. ^{[1
]}

Lee, S. I. ^{[1
]}

Liu, Z. J. ^{[1
]}

Anthony, C. J. ^{[1
]}

Dickey, E. C. ^{[1
]}

Liu, Z. K. ^{[1
]}

Randall, C. A. ^{[1
]}

机构：

[1] Penn State Univ, Dept Mat Sci & Engn, Mat Res Inst, Ctr Dielect Studies, University Pk, PA 16802 USA

来源：

ACTA MATERIALIA | 2006年 / 54卷 / 13期

基金：

美国国家科学基金会;

关键词：

interface reaction; metal-ceramic interface; non-stoichiometry; BaTiO3; MLCC; binder burnout; HRTEM; EELS; CALPHAD;

D O I：

10.1016/j.actamat.2006.03.025

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

This investigation discovers a discrete metallic alloy layer containing Ni, Ti, and Ba between Ni and BaTiO3 co-fired in reducing atmospheres at similar to 1300 degrees C along with an oxygen-depleted zone in BaTiO3 adjacent to the metallic layer. Using high-resolution transmission electron microscopy and electron energy-loss spectroscopy, detailed structural and chemical analyses of the metallic layer are carried out. With complementary thermodynamic approximations, these observations render an assessment of the local effective oxygen partial pressure, which is considerably lower than the external, ambient processing environment. Through a set of model experiments on Ni-BaTiO3-carbon composites, we illustrate that the presence of carbon is sufficient to reduce locally BaTiO3 and form the observed metallic layer at similar to 1300 degrees C. A phase stability analysis indicates that the formation of the Ba and Ni-Ti liquid phases provides a kinetic path for the interfacial reaction. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：3513 / 3523

页数：11

共 32 条

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