| 摘要 |
PROBLEM TO BE SOLVED: To obtain a dielectric porcelain composition having comparatively high εr (relative dielectric constant), large Qu (unloaded quality factor) and a low absolute value of τf (temperature coefficient of resonance frequency). SOLUTION: This dielectric porcelain composition comprises the elements of Ca, RE (a rare earth element such as La or Nd), Ti, Al, Nb and O and is represented by the compositional formula [aCaO-(1/2)bRE2 O3 -cTiO2 -(1/2)dAl2 O3 -(1/2)eNb2 O5 ] (RE is a rare earth element; and each of (a), (b), (c), (d) and (e) is a molar ratio, and a+b+c+d+e=1), wherein 0.2<a<=0.51, 0<=b<=0.3, 0.2<=c<0.325, 0.07<=d<0.3, 0<e<=0.17 and 0.49<=a+b<=0.51; optionally, Ca is substituted with Sr, and Nb is substituted with Ta; also optionally the composition additionally contains MnO2 ; and further optionally, the composition has a perovskite crystal structure. |
