TY - JOUR
T1 - Perovskite-type BaTiO3 ceramics containing particulate SiC
T2 - Part I. Structure variation and phase transformation
AU - Hwang, H. J.
AU - Sekino, T.
AU - Ota, K.
AU - Niihara, K.
PY - 1996
Y1 - 1996
N2 - BaTiO3-based composites with nanosized SiC particulates were successfully fabricated by a hot-pressing technique in an argon atmosphere. Crystal structure and phase transformation behaviour were investigated by X-ray diffraction analysis, linear thermal expansion analysis and internal friction measurement. It was confirmed that the added SiC particulates were uniformly distributed within the matrix BaTiO3 grains, with some larger particulates located at the BaTiO3 grain boundaries. In addition, there were no reaction phases between BaTiO3 matrix and SiC particulates. The crystal structure gradually changed from tetragonal to cubic phase with respect to the SiC content. The Curie temperature, Tc, was lowered as the SiC content increased. Moreover, the transformations in the low-temperature range almost disappeared above 1 vol % SiC. The diffused phase transformation phenomenon was observed as the SiC content increased up to 3 vol %. The results were associated with the grain-size reduction, the existence of oxygen vacancies and the residual stresses associated with the thermal expansion mismatch between matrix and SiC particulate. The influence on the domain structure development of SiC particulates dispersed within the matrix grains was also discussed.
AB - BaTiO3-based composites with nanosized SiC particulates were successfully fabricated by a hot-pressing technique in an argon atmosphere. Crystal structure and phase transformation behaviour were investigated by X-ray diffraction analysis, linear thermal expansion analysis and internal friction measurement. It was confirmed that the added SiC particulates were uniformly distributed within the matrix BaTiO3 grains, with some larger particulates located at the BaTiO3 grain boundaries. In addition, there were no reaction phases between BaTiO3 matrix and SiC particulates. The crystal structure gradually changed from tetragonal to cubic phase with respect to the SiC content. The Curie temperature, Tc, was lowered as the SiC content increased. Moreover, the transformations in the low-temperature range almost disappeared above 1 vol % SiC. The diffused phase transformation phenomenon was observed as the SiC content increased up to 3 vol %. The results were associated with the grain-size reduction, the existence of oxygen vacancies and the residual stresses associated with the thermal expansion mismatch between matrix and SiC particulate. The influence on the domain structure development of SiC particulates dispersed within the matrix grains was also discussed.
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U2 - 10.1007/BF00366360
DO - 10.1007/BF00366360
M3 - Article
AN - SCOPUS:0030241097
VL - 31
SP - 4617
EP - 4624
JO - Journal of Materials Science
JF - Journal of Materials Science
SN - 0022-2461
IS - 17
ER -