MANUFACTURE OF LAMINATED PIEZOELECTRIC MATERIAL

摘要

PURPOSE:To facilitate minimizing the variation of the whole length of a laminated piezoelectric unit along the direction of lamination even if a high load is applied to the end surface of the laminated piezoelectric unit by a method wherein a number of piezoelectric elements which have metal electrodes on their front and rear surfaces are laminated with metal plates between each layer to form the laminated piezoelectric unit and the formed laminated piezoelectric unit is inserted into a case and aged under required conditions. CONSTITUTION:Electrode material such as silver paste is applied to the front and rear surfaces of a disc shape piezoelectric element 101 with predetermined dimensions by screen printing. The applied silver paste is dried and baked. After that, a number of the piezoelectric elements 101 which have metal electrodes 103 on their front and rear surfaces are laminated with metal plates 105 between each layer to form a laminated piezoelectric unit 100. The formed laminated piezoelectric unit 100 is inserted into a suitable case and aged by operating under the conditions same as the most severe conditions under which the laminated piezoelectric unit 100 is used for about 3 hours. By this method, the metal electrodes 103 are made to be dense and gaps between the piezoelectric elements 101 and the metal plates 105 are eliminated.