| 摘要 |
PURPOSE: To provide a dielectric porcelain material having a high dielectric constant εr and excellent in temp. coefft. τf of resonance frequency by adding a specified amt. of PbO to a principal porcelain compsn. contg. BaO, rare earth metal oxides, Bi2 O3 and TiO2 in a specified ratio. CONSTITUTION: PbO is added by 0.01-0.50 pt.wt. to 100 pts.wt. principal porcelain compsn. consisting essentially of BaO, rare earth metal oxides (R2 O3 ) contg. Nd as an essential component, Bi2 O3 and TiO2 are represented by the general formula, aBaO-bR2 O3 -cBi2 O3 -dTiO2 [where a+b+c+d=100mol%, 0.8<=c<=6.3 and (a), (b+c) and (d) are within the region defined by a line connecting four points P, Q, R and S in the diagram] to obtain the objective dielectric porcelain material. At least 85vol.% of this material is rhombic. |
