CAJ | 학술논문

用溶胶一凝胶法制备了La1-xCexMnO3粉体，根据DSC-TGA、FT-IR、XRD分析了样品的晶化过程，用圆柱体法测试了样品的室温电阻率，用微波网络分析仪测试样品的微波吸收性能．结果表明，样品凝胶在煅烧时经过脱水、剧烈分解、逐渐晶化等过程，900％左右形成稳定的钙钛矿结构并伴有少量CeO2杂相；室温电阻率处于半导体范围，且随掺杂量z增加而减小；样品厚度为2．2mm、x=0．4时，13．2GHz频率位置处微波吸收峰值为27dB，10dB频宽为3．2GHz．分析认为，合适的电阻率、钙钛矿晶体极化驰豫及共振、铁磁团簇转向及共振是材料具有良好微波吸收性能的原因．
용용효일응효법제비료La1-xCexMnO3분체，근거DSC-TGA、FT-IR、XRD분석료양품적정화과정，용원주체법측시료양품적실온전조솔，용미파망락분석의측시양품적미파흡수성능．결과표명，양품응효재단소시경과탈수、극렬분해、축점정화등과정，900％좌우형성은정적개태광결구병반유소량CeO2잡상；실온전조솔처우반도체범위，차수참잡량z증가이감소；양품후도위2．2mm、x=0．4시，13．2GHz빈솔위치처미파흡수봉치위27dB，10dB빈관위3．2GHz．분석인위，합괄적전조솔、개태광정체겁화치예급공진、철자단족전향급공진시재료구유량호미파흡수성능적원인．
The powder samples of La1-xCexMnO3 were prepared by sol-gel method and their crystallization process was discussed on the basis of DSC-TGA, XRD and FT-IR. Their con- ductivities at room temperature and microwave absorption properties were measured respec- tively by cylinder method and microwave network analyzer. The results show that the gel of La1-xCexMnO3 went through dehydration, severe decomposition and gradual crystallization and transformed into a stable perovskite structure with a small amount of CeO2 impurity phase about 900℃ when calcined. The resistivites of the samples were within semicon- ductor area and reduced with Ce content x increase. The effective absorption bandwidth a- bove 10 dB for La1-xCexMnO3 was 3.2 GHz and the absorption peak was 27dB at 13.2 GHz when the thickness was 2.2 mm and x = 0.4. From the analysis,it is believed that La1-xCexMnO3 has excellent microwave absorption because of appropriate resistivity, polarization relaxation and resonance of perovskite crystal, and turning and resonance of ferromagnetic clusters in the sample under microwave electromagnetic field.