Abstract: A method for manufacturing piezoelectric ceramic including the steps of: preparing a raw material so as to contain A, B, Ba and Zr as major constituents in a composition ratio represented by the following formula: (1-s)ABO3-sBaZrO3 (where A is at least one element selected from alkali metals, B is at least one of transition metal elements and includes Nb, 0.06<s?0.15); molding the raw material to obtain a molded body; sintering the molded body in a reducing atmosphere; and subjecting a sintered body obtained at the sintering step to a heat treatment in an oxidative atmosphere.

Abstract: There is provided an anisotropically shaped powder preferred as plate-like crystals used in the process of producing niobate-based KNbO3—NaNbO3—LiNbO3-based crystal-oriented ceramics and the like, and a method for producing the same. The production method includes, an oxide powder, such as Nb2O5, and a surfactant are added to an aqueous solution of alkali hydroxides, such as NaOH and KOH to perform hydrothermal synthesis, the product obtained after this reaction is washed with an organic solvent, and further, the product after the washing is fired at 170° C. to 700° C. In addition, according to this production method, it is possible to obtain an anisotropically shaped powder having a ratio of an average particle length in a major axis direction to an average particle length in a thickness direction in the range of 2 to 20 and having a pseudo-cubic perovskite structure in which a crystal face is oriented in a (100) plane.

Abstract: A piezoelectric ceramic contains as a main component an oxide which is represented by the general formula: sA1B1O3-t(Bi.A2)TiO3-(1-s-t)BaMO3 (where A1 is at least one element selected from among alkali metals; B1 is at least one element selected from among transition metal elements and contains Nb; A2 is at least one element selected from among alkali metals; and M is at least one element selected from the 4A group and contains Zr). In the general formula, s and t satisfy 0.905?s?0.918, 0.005?t?0.02, and a piezoelectric constant d33(25) at 25° C. and a piezoelectric constant d33(200) at 200° C. satisfy the relationship (d33(25)?d33(200)/d33(25)?0.13.

Abstract: There is provided an anisotropically shaped powder preferred as plate-like crystals used in the process of producing niobate-based KNbO3—NaNbO3—LiNbO3-based crystal-oriented ceramics and the like, and a method for producing the same. The production method includes, an oxide powder, such as Nb2O5, and a surfactant are added to an aqueous solution of alkali hydroxides, such as NaOH and KOH to perform hydrothermal synthesis, the product obtained after this reaction is washed with an organic solvent, and further, the product after the washing is fired at 170° C. to 700° C. In addition, according to this production method, it is possible to obtain an anisotropically shaped powder having a ratio of an average particle length in a major axis direction to an average particle length in a thickness direction in the range of 2 to 20 and having a pseudo-cubic perovskite structure in which a crystal face is oriented in a (100) plane.