| 摘要 |
Barium titanate based dielectric compositions having the general formula Ba(1-x-x'-x'')PbxCax'Srx''Ti(1-y-y'-y'')SnyZry,Hfy',O3, wherein x, x', x'' and y, y', y'' represent mole fractions of the divalent and tetravalent cations and have independent values greater than zero and less than 0.3, such that the sums (x + x' + x'') and (y + y' + y'') do not exceed 0.4. Regardless of the specific composition selected, the coforms of the invention have a mean primary particle size in the range of 0.05 to 0.4 microns with a very narrow particle size distribution. The products are dispersible so that the mean particle size determined by image analysis and by sedimentation are comparable. The mole ratio of the divalent to tetravalent cations of the coforms is 1.000 ? 0.015 notwithstanding the number nor mole percent of the divalent and tetravalent cation substitutions. |
