| 摘要 |
PURPOSE:To obtain the porcelain composition having a high dielectric constant and insulation resistance and is small in the rate of a change in the dielectric constant with temp. by compounding three main components magnesium lead titanate, lead titanate and nickel lead niobate so as to be kept within a specific compsn. range and adding a prescribed ratio of lead strontium niobate as an auxiliary component thereto. CONSTITUTION:The lead oxide, magnesium oxide, tungsten oxide, niobium oxide, nickel oxide, titanium oxide and strontium carbonate are used as starting raw materials. The respective raw materials are so compounded as to attain the range shown by diagonal lines in a ternary compsn. diagram and the compsn. range existing on boundary lines. The lead strontium niobate is added as the auxiliary component thereto in such a manner that the content thereof attains 0.01 to 30mol%. After this mixture is mixed by a wet process in a ball mill, etc., the mixture is calcined at 750 to 850 deg.C. The resulted powder is pulverized by a ball mill, etc., and an org. binder is added thereto after filtering and drying. The powder is pressed after sizing, by which a molding is obtd. The molding is sintered for about one hour at 1000 to 1100 deg.C. |
