Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Thermal Decomposition and Sintering Characteristics of Cr-Deficient $(La,Ca)CrO_3$

크롬부족 (란탄, 칼슘)크로마이트의 열분해과정 및 소결특성

  • 이상기 (경상대학교 공과대학 전자재료공학과, 첨단소재연구소) ;
  • 조성걸 (경상대학교 공과대학 전자재료공학과, 첨단소재연구소)
  • Published : 1997.11.01
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Abstract

La0.8Ca0.2Cr0.98O3 powder was prepared using the modified Pechini process. Various crystalline phases formed during thermal decomposition were investigated. (La,Ca)CrO4 phase, first formed from the precursor, was transformed to (La,Ca)CrO3 and CaCrO4 above 80$0^{\circ}C$, which remained up to 110$0^{\circ}C$. However, only (La,Ca)CrO3 phase consisting of orthorhombic and intermediate rhombohedral polymorphs was observed after sintering at 125$0^{\circ}C$. The specimens sintered at 140$0^{\circ}C$ exhibited 98% of relative density and rather wide grain size distribution with average grain size of 3-4 ${\mu}{\textrm}{m}$. Densification and grain growth of the specimens observed above 125$0^{\circ}C$ were presumably attributed to liquid phase sintering resulted from melting of Ca3(CrO4)2 phase.

Keywords

References

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