| 摘要 |
PURPOSE: To provide a dielectric porcelain compsn. having a relative dielectric constant of >=2,500, <=1,300 deg.C firing temp., temp. variation of capacitance satisfying X7R of EIA standard, such a small dielectric loss as <=2.5%, low voltage dependency and >=10<4> MΩinsulation resistance. CONSTITUTION: This dielectric porcelain compsn. contains 0.8-2.5 pts.wt. Nb2 O5 , 0.06-0.70 pts.wt. MgO, 0.005-0.520 pt.wt. Tb4 O7 or Sm2 O3 and 0.01-0.30 pt.wt. (expressed in terms of MnCO3 ) MnO on the basis of 100 pts.wt. BaTiO3 . The molar ratio of Nb2 O5 to MgO is 0.5-2.2. This compsn. preferably contains 0.05-0.50 pt.wt. at least one of SiO2 and Al2 O3 and <=0.5 pt.wt. ZnO on the basis of 100 pts.wt. BaTiO3 . |
