Abstract
Porous Y-doped (Ba,Sr)TiO3 ceramics were prepared by the spark plasma sintering of (Ba,Sr)TiO3 powders with different amounts of carbon black, and by subsequently burning out the carbon black acting as a pore precursor. The microstructure, PTCR and gas-sensing characteristics for porous Y-doped (Ba,Sr)TiO3 ceramics were investigated. Spark plasma sintered (Ba,Sr)TiO3 ceramics revealed a very fine microstructure containing submicron-sized grains with a cubic phase and revealed an increased porosity after the carbon black was burned out. As a result of reoxidation treatment, the grain size of the (Ba,Sr)TiO3 ceramics increased to a few and mu;m and the cubic phase transformed into a tetragonal phase. The phase transformation of (Ba,Sr)TiO3 ceramics was affected by grain size. The PTCR jump in the (Ba,Sr)TiO3 ceramics prepared by adding 40 vol.% carbon black showed an excellent value of 4.72 and times; 10 6 , which was ten times higher than the PTCR jump in (Ba,Sr)TiO3 ceramics. The electrical resistivity of the porous (Ba,Sr)TiO3 ceramics was recovered as the atmosphere changed from a reducing gas (N2) to an oxidizing gas (O2) under consecutive heating and cooling cycles.
Original language | English |
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Pages (from-to) | 93-98 |
Number of pages | 6 |
Journal | Metals and Materials International |
Volume | 16 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2010 Feb |
Bibliographical note
Funding Information:This work was financially supported by the program Development of Basic Technology for Next Generation Li-Composite Secondary Batteries of KIST.
Keywords
- Electrical properties
- Grain boundary
- Grain growth
- Microstructure
- Sintering
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys
- Materials Chemistry