Title :
Influence of sintering condition on microstructure development of BaTiO3 based PTCR materials
Author :
Huang, Z.Z. ; Lu, H.M. ; Yin, Z.W.
Author_Institution :
Shanghai Inst. of Ceramics, China
fDate :
30 Aug-2 Sep 1992
Abstract :
The influence of sintering conditions on the microstructure development of the (Ba-Sr)TiO3 system was studied. Experimental results show that the samples were densified at a rather low temperature without substantial grain growth. As the temperature increased, both discontinuous and continuous grain growth took place, depending mainly on the temperature range and heating rate of the sintering schedule, i.e., nucleation and grain growth processes. A good PTCR (positive temperature coefficient of resistivity) characteristic was observed for samples having a grain size of 5-10 μm. Compared to the normal process for the (Ba-Pb)TiO3 system, sintering in nitrogen and cooling in air produces a finer grain microstructure, resulting in decreased resistivity and an improved PTCR characteristic. SIMS (secondary ion mass spectrometry) and EPMA (electron-probe microanalysis) indicated that the additive ions are mainly deposited at grain boundary and intragranular regions
Keywords :
barium compounds; ceramics; electrical conductivity of solids; electron probe analysis; ferroelectric materials; grain boundaries; grain growth; grain size; nucleation; powder technology; secondary ion mass spectra; sintering; 5 to 10 micron; BaSrTiO3; EPMA; N2 sintering; PTCR; SIMS; air cooling; electron-probe microanalysis; grain boundary; grain growth; grain microstructure; grain size; heating rate; intragranular regions; nucleation; positive temperature coefficient of resistivity; secondary ion mass spectrometry; sintering conditions; Conductivity; Cooling; Grain boundaries; Grain size; Heating; Mass spectroscopy; Microstructure; Nitrogen; Temperature dependence; Temperature distribution;
Conference_Titel :
Applications of Ferroelectrics, 1992. ISAF '92., Proceedings of the Eighth IEEE International Symposium on
Conference_Location :
Greenville, SC
Print_ISBN :
0-7803-0465-9
DOI :
10.1109/ISAF.1992.300587
