| 摘要 |
PROBLEM TO BE SOLVED: To provide a polarization processing method for an oxide-based inorganic piezoelectric material sintered body for ultrasonic thickness sensor that obtains piezoelectric characteristics necessary for an ultrasonic thickness sensor without dipping in silicone oil as a sintered body polarization processing method when manufacturing an ultrasonic thickness sensor which is made of an oxide-based inorganic piezoelectric material and makes the density of the sintered body low so as to exhibit flexibility and that is suitable for a mass-production process, a sintered body polarized by the same, and a polarization processing device.SOLUTION: When a laminar sintered body which is made of an oxide-based inorganic piezoelectric material used as a piezoelectric body of an ultrasonic thickness sensor, and has a density of 70-80% is subjected to polarization processing, an electrode for corona discharge is arranged opposite a plate surface of a base electrode on a flat plate, a voltage is applied between the electrode for corona discharge and the base electrode with a laminar sintered body arranged on the base electrode to generate a corona discharge therebetween, and the laminar sintered body is exposed to within an electric field region formed by the corona discharge to performs the polarization processing on the lamina sintered body. |
