Positive‐Temperature‐Coefficient Effect in Graphite–Cristobalite Composites
- 1 July 1992
- journal article
- Published by Wiley in Journal of the American Ceramic Society
- Vol. 75 (7) , 1772-1776
- https://doi.org/10.1111/j.1151-2916.1992.tb07196.x
Abstract
An anomalous positive temperature coefficient (PTC) of resistance was found in a conductor–insulator ceramic composite. The composite materials was composed of randomly dispersed conducting graphite and insulating cristobalite‐form SiO2 particles. The PTC effect occurred at exactly 230°C, that is, at a reversible phase inversion point with a large thermal expansion of cristobalite. The magnitude of the PTC anomaly was high in composites located in the middle of the percolation curve, and loaded with large graphite and fine SiO2 particles.Keywords
This publication has 11 references indexed in Scilit:
- Electron transport processes in conductor‐filled polymersPolymer Engineering & Science, 1983
- Temperature effect on the electrical resistivity of metal/polymer compositesPolymer Engineering & Science, 1978
- Stability of polymer composites as positive‐temperature‐coefficient resistorsPolymer Engineering & Science, 1974
- Percolation and ConductionReviews of Modern Physics, 1973
- A new class of switching materialsJournal of Applied Physics, 1973
- Influence of Particle Size on the Electrical Resistivity of Compacted Mixtures of Polymeric and Metallic PowdersJournal of Applied Physics, 1971
- A New Resistor Having An Anomalously Large Positive Temperature CoefficientJapanese Journal of Applied Physics, 1971
- Some aspects of semiconducting barium titanateSolid-State Electronics, 1964
- Resistivity Anomaly in Doped Barium TitanateJournal of the American Ceramic Society, 1964
- Properties of Semiconductive Barium TitanatesJournal of the Physics Society Japan, 1959