Stack-type piezoelectric element and process for production thereof.

摘要

In an overall stacked piezoelectric element, the material for the electrodes (2a, 2b) was selected from aluminum, nickel and copper each alone or alloys based on aluminum, nickel or copper, and further the parts (4a, 4b) of the electrodes (2a, 2b) which contact with molding resin on the side face of the stacked body and the parts (4a, 4b) which have to be insulated from the lead-out terminals (3a, 3b) were subjected to an oxidation or nitriding treatment. As the result, an improved element was obtained which is of a high reliability, suited to low voltage operation and suffers no short-circuit of the electrodes (2a, 2b) even when water permeates to the side face of the stacked body during operation in humid atmosphere.