Fabrication and PTCR Characteristics of Porous Barium Titanate Thermistors using Graphite Powders

  • 발행 : 1996.12.01

초록

New porous BaTiO$_3$ thermistors were fabricated using graphite powders (0 to 10 wt. %) and their porosities were in the range of 9.1% to 16.2%. As results of impedance analysis, it was confirmed that the pores affected the grain-boundary resistance and the bulk (grain interior) resistance was constant as about 25 $\Omega$ at room temperature. The magnitude of PTCR effect $(p_{max}/p)$ markedly increased from 3 orders to 7 orders without addition of any acceptor dopant such as Mn or Cr.

키워드

참고문헌

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