复合助烧剂对CaO-BaO-Li_2O-Sm_2O_3-TiO_2陶瓷低温烧结和性能的影响

采用传统固相反应法制备了CaO-BaO-Li_2O-Sm_2O_3-TiO_2(CBLST)陶瓷。研究了复合添加BaCu(B_2O_5)(BCB)和Li_2O-B_2O_3-SiO_2(LBS)对CBLST陶瓷的烧结特性、微观组织、相组成及介电性能的影响。结果表明:添加质量分数w(BCB)=60%和w(LBS)=0.5%～5.0%的CBLST陶瓷的相组成未改变,仍为正交钙钛矿相和BaSm_2Ti_4o_(12)(BST)相。通过添加w(BCB)=6.0%和w(LBS)=0.5%,可以使CBLST陶瓷的烧结温度从1325℃降到1050℃,并且在1050℃烧结2h的CBLST陶瓷介电性能优良:ε_r=81.9,tanδ=0.0062,τ_f=–3.75×10~(–6)/℃,其tanδ比纯CBLST陶瓷的tanδ(0.016)明显降低。

Effects of complex sintering agent on low temperature sintering and properties of CaO-BaO-Li2O-Sm2O3-TiO2 ceramics

CaO-BaO-Li2O-Sm2O3-TiO2(CBLST) ceramics were prepared by conventional solid-state reaction method. Effect of BaCu(B2O5)(BCB) and Li2O-B2O3-SiO2(LBS) complex additive on the sintering behaviors, microstructure, phase composition and dielectric properties of the CBLST ceramics were investigated. The results show that the CBLST ceramics possess two phases of orthorhombic perovskite and BST phase when adding with w(BCB)=6.0% and w(LBS)=0.5%～5.0% additive. The sintering temperature of the CBLST ceramics is reduced from 1 325 ℃ to 1 050 ℃ and the excellent dielectric properties of εr=81.9, tanδ=0.006 2, τf =–3.75×10–6 ℃ are obtained with w(BCB)=6.0% and w(LBS)=0.5% doped CBLST ceramics sintered at 1 050 ℃ for 2 h. The dielectric loss of w(BCB)=6.0% and w(LBS)=0.5% doped CBLST ceramics is lower obviously than that of pure CBLST ceramics (tanδ=0.016).