| 摘要 |
PURPOSE:To obtain fine powder of an easily sinterable compound composed of lead ferroniobate and lead ferrotungstate, by preliminarily precipitating necessary minimum amount of lead component and whole tungsten in the form of tungstate and precipitating the remaining components. CONSTITUTION:A perovskite-type compound composed of lead ferroniobate and lead ferrotungstate is produced by the following method. Lead tungstate is precipitated from a necessary minimum amount of a lead component and whole tungsten component to obtain a slurry solution. An aqueous solution of iron component and niobium component of amounts necessary for attaining objective composition is added to the above slurry solution and an iron-niobium coprecipitate is formed from the mixed solution. A precipitate mixture composed of precipitate of lead tungstate and coprecipitate of iron and niobium can be produced by this process. A precipitate of whole components is produced either by (1) adding an aqueous solution of a lead component of an amount to achieve the objective composition to the aqueous medium of the above mixed precipitate thereby forming a precipitate of a lead component or (2) mixing the mixed precipitate with powdery lead compound of the same kind and same amount as the above lead compound. The obtained precipitate is washed with water, filtered, dried and calcined at 400-1,000 deg.C.
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