| 摘要 |
(1) A single crystal, solid solution, chemically homogenous powder that comprises a perovskite compound having useful electrical properties and the general formula: ABO3, wherein the perovskite compound is selected from the group consisting of lead zirconate titanate, lead lanthanum zirconate titanate, lead titanate, lead zirconate, barium titanate, lead magnesium niobate, or lead zinc niobate, and having 0-50 percent total dopant or solid solution substitutions; and wherein when lead zirconate titanate is selected the perovskite has the general formula: Pb(Zr1-xTix)O3, wherein x has a value of: (1) between 0 and 0.44; (2) between 0.44 and 0.55, and a total dopant and solid solution substitution level between 13 and 50 mole percent; (3) between 0.55 and 1.00. A process for making a crystalline ceramic powder having a perovskite structure, ABO3, that includes the steps of preparing a first acidic solution containing one or more elements selected from the group consisting of hafnium, zirconium, titanium, niobium, tantalum, uranium, iron, antimony, lanthanum, bismuth, thorium, indium, nickel, manganese, neodymium, samarium, cobalt, tungsten, tin, vanadium, dysprosium, praseodymium, yttrium, promethium, europium, cerium, ytterbium, lutetium, scandium, gadolinium, terbium, holmium, erbium, thulium, chromium, potassium, and lithium; preparing a second basic solution containing a sufficient concentration of hydroxide to provide a predetermined pH when mixed with the first solution; adding the first acidic solution to the second basic solution to precipitate a substantially pure mixture of hydroxides; washing the precipitate to remove hydroxide and salt impurities that solubilize lead or other constituent elements of the powder; preparing an aqueous slurry of the washed precipitate and adding oxides or hydroxides of one or more of (2) the elements selected from the group consisting of barium, strontium, calcium, magnesium, lead, zinc, yttrium, magnesium, manganese, cobalt, zinc and nickel; hydrothermally treating the slurry at an elevated temperature and pressure for a time sufficient to form the powder; and drying the powder; wherein when lead, zirconium and titanium are selected the perovskite has the general formula: Pb(Zr1-xTix)O3, wherein x has a value of: (1) between 0 and 0.44; (2) between 0.44 and 0.55, and a total dopant and solid solution substitution level between 13 and 50 mole percent; (3) between 0.55 and 1.00; and wherein when x has a value of (1) or (3) then the total dopant and solid substitution level ranges from 0 to 50 mole percent.
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