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研究了烧结温度、组成和稀土元素对(1-x)CaTiO_3-x(Li_(1/2)Ln_(1/2))TiO_3(x=0.3、0.5(摩尔分数); Ln=La、Nd、Sm)微波介质陶瓷的晶体结构和微波介电性能的影响.X-射线衍射(XRD)分析表明,除(1-x)CaTiO_3-x(Li_(1/2)Ln_(1/2))TiO_3(x=0.5,Ln=Nd)陶瓷中含有少量Nd_2Ti_2O_7外,其余陶瓷均形成了单一的正交钙钛矿相.x=0.5的样品微波介电性能明显优于相应的x=0.3的样品.(1-x)CaTiO_3-x(Li_(1/2)Ln_(1/2))TiO_3(x=0.5)陶瓷微波介电性能:介电常数ε=160,品质因数与频率之积Qf =1 200 GHz,频率温度系数τ_f=-97×10~(-6)/℃(Ln=La);ε=129,Qf=2 000 GHz,τ_f=-52×10~(-6)/℃(Ln=Nd);ε=118,Qf=2 305 GHz,τ_f=-45×10~(-6)/℃(Ln=Sm).“,”The effects of sintered temperature, composition and rare earth ions on the crystal structure and microwave dielectric properties of (1-x)CaTiO_3-x(Li_(1/2)Ln_(1/2))TiO_3(x=0.3, 0.5; Ln=La, Nd, Sm) ceramics were investigated. From the X-ray diffraction patterns, orthorhombic perovskite phase was formed in ceramics, while the second phase Nd_2Ti_2O_7 was formed in (1-x)CaTiO_3 -x(Li_(1/2)Ln_(1/2))TiO_3(x= 0.5; Ln=Nd) ceramic. The microwave dielectric properties of the samples at x=0.5 are better than that of the samples at x=0.3. (1-x)CaTiO_3-x(Li_(1/2)Ln_(1/2))TiO_3(x=0.5; Ln=La, Nd, Sm) ceramics display the microwave properties as follows: ε=160,Qf=1 200 GHz,τ_f=-97×10~(-6)/℃ for Ln=La;ε=129,Qf=2 000 GHz,τ_f=-52×10~(-6)/℃ for Ln=Nd;ε=118,Qf=2 305 GHz,τ_f=-45×10~(-6)/℃ for Ln=Sm.