Microstructures and LPG Sensing Properties of Maghemite(${\gamma}-Fe_2O_3$) Ceramics

마게마이트(${\gamma}-Fe_2O_3$) 소결체의 미세구조와 LPG 감지특성

  • 신형섭 (포항공과대학 재료·금속공학과) ;
  • 오재희 (인하대학교 무기재료공학과)
  • Published : 1992.06.01

Abstract

The microstructur and LPG sensing properties of maghemite (${\gamma}-Fe_2O_3$) ceramics have been studied. The acicular and fine spherical shaped iron oxide particles were sintered at below $900^{\circ}C$. The maghemite ceramics were prepared by reduction-oxidation of sintered iron oxide. With the microstructure of acicular and/or fine grains, the maghemite ceramics have good LPG sensing properties. Increased sintering temperature deteriorates the LPG sensitivity of maghemite ceramics due to the grain growth. The maghemite ceramics prepared from the mixed iron oxide, of a large amount of acicular particles and a small amount of spherical ones, have a lower LPG sensitivity than that of the acicular iron oxide ceramics. But, they seem to be of higher mechanical strength. The optimum working temperature for LPG sensing of the maghemite ceramics was found to be $300~350^{\circ}C$.

Keywords

References

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