摘要
以聚乙烯醇为聚合剂,采用湿化学法制备含Li-Co-Ti-P-O助烧结剂的BaTi0.8Co0.2O3-δ热敏陶瓷粉体,研究Li-Co-Ti-P-O助烧剂对BaTi0.8Co0.2O3-δ热敏陶瓷烧结性能和电阻温度特性的影响。通过扫描电镜和X射线衍射仪观察和分析该陶瓷材料的微观形貌和物相组成,用热分析仪测试其差热-热重曲线,用电阻-温度特性测试仪测定其电子导电性随温度的变化特性。结果表明,添加适量的Li-Co-Ti-P-O助烧剂能使BaTi0.8Co0.2O3-δ陶瓷的烧结性得到明显改善,烧结温度由1 300℃降到950℃。该陶瓷材料的室温电阻率由7.56×105Ω·cm减小到8.83×104Ω·cm。材料常数B大于3 100 K,助烧剂对其几乎没有影响。
To decrease the sintering temperature of the novel BaTi0.8Co0.2O3-δ-based ceramics with a negative temperature coefficient(NTC),BaTi0.8Co0.2O3-δ powders with Li-Co-Ti-P-O sintering additive were prepared by a wet chemical process polymerized with polyvinyl alcohol.The influence of Li-Co-Ti-P-O sintering additive on the sinter-ability and resistance-temperature characteristics of the BaTi0.8Co0.2O3-δ-based ceramics was also investigated.X-ray diffraction was used to analyze the phase component,thermal analyzer was applied to test the DSC/TG curve,SEM was used to observe the microstructure and resistance-temperature measurement system was applied to investigate the temperature dependence of electrical conductivity.The results show that,when the Li-Co-Ti-P-O sintering additive is added,the sintering temperature of BaTi0.8Co0.2O3-δ ceramics decreases from 1 300 ℃ to 950 ℃,the ceramic density is improved,and the room-temperature resistivity decreases from 7.56×105 Ω·cm to 8.83×104 Ω·cm.The sintering additive does not affect the material constant B.The material constants of both ceramics with and without sintering additive are higher than 3 100 K.
出处
《粉末冶金材料科学与工程》
EI
2011年第4期511-516,共6页
Materials Science and Engineering of Powder Metallurgy
基金
国家自然科学基金(面上)资助项目(50872155)
粉末冶金国家重点实验室开放课题