微波介质陶瓷的低温烧结研究.docx

文章编号：1000-324X(2008)0？-0???-0?
Ca0.3(Li1/2Sm1/2)0.7TiO3微波介质陶瓷的低温烧结研究
李月明1，宋婷婷1，尤源2，胡元云2，刘维良1，唐春宝1
（1.景德镇陶瓷学院，江西景德镇，333001；2.浙江正原电气股份有限公司，浙江嘉兴，314003）
摘要：采用传统陶瓷制备工艺，制备了掺杂Na2O–CaO–B2O3（NCB）氧化物的Ca0.3(Li1/2Sm1/2)0.7TiO3（CLST）陶瓷，研究了NCB掺杂量与晶相组成、显微结构、烧结性能及微波介电性能的关系。研究结果表明复合氧化物NCB掺杂量在1～15wt%范围内没有杂相生成，晶相仍呈斜方钙钛矿结构。随着NCB添加量的增加，陶瓷致密化温度和饱和体积密度降低，介电常数εr、无载品质因数与谐振频率乘积Qf值也呈下降趋势，频率温度系数τf向正方向增大。NCB氧化物掺杂能有效地将CLST陶瓷的烧结温度由1300℃降低至900℃。添加12.5wt%NCB的CLST陶瓷在低温900℃烧结5h仍具有良好的微波介电性能：εr＝73.7，Qf＝1583GHz，τf＝140.1ppm/℃，满足高介多层微波器件的设计要求。
关键词：Ca0.3(Li1/2Sm1/2)0.7TiO3；Na2O–CaO–B2O3；低温烧结；微波介质陶瓷
中图分类号：TM227文献标识码：A
ResearchonLow-temperatureSinteringofCa0.3(Li1/2Sm1/2)0.7TiO3MicrowaveDielectricCeramics
LiYue-ming1,SongTing-ting1,YouYuan2,HuYuan-yun2,LiuWei-liang1,TangChun-bao1
(1.JingdezhenCeramicInstitute,Jingdezhen,333001,China;2.ZhejiangZhenyuanElectricCo.Ltd.,Jiaxing,314003,China)
Abstract:TheNCB(Na2O–CaO–B2O3)-dopedCa0.3(Li1/2Sm1/2)0.7TiO3(CLST)ceramicswerefabricatedviathetraditionalceramicprocess.TherelationbetweenNCBdopantcontentsandthecrystalstructure,microstructure,sinteringbehavior,anddielectricpropertiesofCLSTceramicswereinvestigatedsystematically.Theresultsindicatethatthesecondphasesarenotfoundwithin1~15wt%rangeofNCBdopantcontentsandthemajorphaseofCLSTceramicsisstillorthorhombicperovskite.WiththeincreaseofNCBcontent,thedensificationtemperatureandbulkdensityofCLSTceramicsdecrease,thedielectricconstantεrandtheproductofqualityfactorandresonancefrequencyQfvaluealsodecrease,andthetemperaturecoefficientofresonantfrequencyτfincreasestopositive.NCBcaneffectivelydecreasethesinteringtemperatureofCLSTfrom1300℃to900℃.ThesampleofCLSTwith12.5wt%NCBsinteredat900℃for5hstillhasexcellentdielectricproperties:εr＝73.7，Qf＝1583GHz，τf＝140.1ppm/℃.Thedesigndemandofhighdielectricconstantandmultilayermicrowavecomponentsaresatisfied.
Keyword:Ca0.3(Li1/2Sm1/2)0.7TiO3;Na2O–CaO–B2O3;low-temperaturesintering;microwavedielectricceramic1引言
近年来随着通讯技术的迅猛发展，移动通信设备和便携式终端正趋向小型化、轻量化、集成化、高可靠性和低成本方向发展，这对以微波介质陶瓷为基础的微波电路元器件提出了更高的要求[1]。因