【摘要】 采用传统电子陶瓷的制备方法,系统研究了(1-x)PbNb2O6-xCaTiO3(x=0、0.01、0.02、0.03、0.04)系高居里温度压电陶瓷。XRD分析表明,x=0时,材料只能形成三方非铁电相钨青铜结构,而x在0.01~0.04mol范围内均能形成钨青铜型固溶体,利用XRD数据计算了晶体的晶格常数随x的变化,发现随着CaTiO3含量增加,晶胞体积减小。陶瓷材料的居里温度测试结果表明该体系具有高的居里温度(Tc>400℃)。测试了不同组成陶瓷的压电、介电性能,CaTiO3的掺杂量为x=0.03时陶瓷样品的压电常数达到d33=64pC/N,平面机电耦合系数kp=0.269,材料的介电常数ε33T/ε0=293,介质损耗tanδ=0.021,居里温度Tc=570℃,该组成具有优异的压电性能,适合于高温环境下的使用。更多还原

【Abstract】 (1-x)PbNb2O6-xCaTiO3(x=0,0.01,0.02,0.03,0.04) system with high Curie temperature piezoelectric ceramics were fabricated by traditional ceramic technique.XRD results show rhombohedral tungsten bronze non-ferroelectric solid solution is obtained when x=0.While x=0.01-0.04,the orthorhombic symmetry tungsten bronze structure with ferroelectric characteristic existed in these compositions.The lattice constant of crystals were calculated from XRD data.It is found that the lattice constant and the unit-cell volume decrease with the increasing of dopant CaTiO3 content.The dependence of dielectric constant and temperature shows that all the compositions have a high Curie temperature above 400℃.The piezoelectric properties of PbNb2O6 ceramics have been enhanced by doping CaTiO3.When x=0.03,the piezoelectric constant d33 reaches to 64pC/N which is the maximum of all the compositions,and the planar electromechanical coupling factor kp is 0.269,the dielectric constant ε33T/ε0 is 293,the dielectric loss tan δ is 0.021 and the Curie temperature reaches to 570℃.This material is desirable for high temperature application.更多还原