MONOMORPH-TYPE PIEZOELECTRIC/ELECTROSTRICTIVE ELEMENT AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: TANAKA RITSU, YAMAGUCHI HIROFUMI, OZAWA SHUICHI, YURA YUKINOBU
• Format: Patent
• Language: English
• Published: 08.05.2008
• Subjects: ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; CORRECTION OF TYPOGRAPHICAL ERRORS; ELECTRICITY; i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; LIME, MAGNESIA; LINING MACHINES; METALLURGY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PERFORMING OPERATIONS; PHYSICS; PRINTING; REFRACTORIES; SELECTIVE PRINTING MECHANISMS; SLAG; STAMPS; TRANSPORTING; TREATMENT OF NATURAL STONE; TYPEWRITERS

PROBLEM TO BE SOLVED: To provide a monomorph-type piezoelectric/electrostrictive element composed of a non-lead based piezoelectric/electrostrictive crystalline body, and to provide a method for manufacturing this. SOLUTION: This monomorph-type piezoelectrc/electrostrictive element is formed of a piezoelectric/electrostrictive body as a non-lead based piezoelectric/electrostrictive crystalline body containing at least Nb, Ta, and one or more types of alkali metal element, which has a tetragonal crystal structure, at a temperature higher than the phase transition point and at least any one of tetragonal and prismatic crystal structures at a temperature lower than the phase transition point, and which is curved to a larger extent by polarization treatment to take on a curved shape at a temperature lower than that of phase transition point. In the polarization treatment, electric field is increased at the electric field increase rate, from 0.1 (kV/mm)/sec or larger to 5 (kV/mm)/sec or smaller, with applying the maximum electric field of from 2 kV/mm or larger to 10 kV/mm or smaller, and the piezoelectric/electrostrictive body assumes a curved shape, in such a state that electric field will not be applied after the polarization treatment. COPYRIGHT: (C)2008,JPO&INPIT