Rare Earth and Perovskite Composite Ceramics Applied for the Thermistor with Wide Temperature Range
| Autor: | Bo Zhang, Ai Min Chang, Qing Zhao, Pengjun Zhao, Fang Guan |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Materials science
Mechanical Engineering Thermistor Composite number Analytical chemistry Mineralogy Atmospheric temperature range Mechanics of Materials Electrical resistivity and conductivity visual_art Phase (matter) visual_art.visual_art_medium General Materials Science Orthorhombic crystal system Ceramic Perovskite (structure) |
| Zdroj: | Key Engineering Materials. :613-616 |
| ISSN: | 1662-9795 |
| DOI: | 10.4028/www.scientific.net/kem.512-515.613 |
| Popis: | Different compositions (aY2O3+bCeO2)-0.4YCr0.5Mn0.5O3 (a+b=0.6) were prepared via a conventional solid-state reaction at 1200°C, and sintered under air atmosphere at 1600°C. XRD patterns analysis has revealed that for 02O3, CeO2 and orthorhombic perovskite YCr0.5Mn0.5O3 phase, respectively. SEM and EDAX observations confirm the obtaining of three-phased composite ceramics. The brighter regions are the Y2O3 and CeO2 phase, whereas the darker are perovskite phase. All the NTC thermistors prepared show a similar linear relationship between the ln of the resistance and the reciprocal of the absolute temperature, indicative of NTC characteristics. For 0≤a≤0.6, the plotting curves of resistance- temperature characteristic are none linear on the wide temperature range, exhibit two branches. The obtained B25/150 and B700/1000 constants of the thermistors are in the range 3600-4400K and 6700-12000K. The magnitude order of the resistivity at 25°C is of 106-107Ωcm and activation energies vary from 0.313 to 1.029 eV at low and high temperatures, respectively. These compounds, having good NTC characteristics in a wide range of temperatures, could be applied as potential candidates for NTC thermistors from ambient to 1100°C. |
| Databáze: | OpenAIRE |
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