采用固相合成法制备了(Na0.5Ko.5)Nb()3(KNN)掺杂的(Bao.。2Cao.。8)(Ti0.95Zro.05)03(BCZT)陶瓷.研究了KNN掺杂量对BCZT物相结构、晶粒生长和介电性能的影响.XRD结果表明BCZT—χKNN陶瓷可形成单一钙钛矿结构的固溶体,Nb汁离子取代Ti^4+位,Na+,K+取代Ba2+位,并在晶界处发生偏析,从而使得烧结温度降低,介温峰变宽.KNN固容量的增加直接影响陶瓷微观结构、晶粒尺寸和介电性能,并且在KNN固容量为4%时陶瓷具有明显弛豫现象和最大介电常数(Е=6ooo).
Lead-free (Bao. 9z Ca0.0s ) (Tio. 95 Zr0.0s ) O3-x (Nao. 5 K0. s ) NbO3 (BCZT-xKNN) ceramics were prepared successfully using a solid-state reaction technique. The effect of KNN content on structure, grain growth and dielectric properties were studied. XRD results show that BCZT-xKNN ceramics are pure perovskite structure and no second phase are detected. The KNN content causes inhibition of grain growth and downward shift of Curie temperature (To). The highest dielectric constant (t'----6 330) are obtained for the samples at x----0.04.