MULTILAYER PIEZO-ELECTRIC TRANSDUCER AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To eliminate irregularity of compression stress when a plurality of piezo-electric boards are stacked through an electrode board by interposing an electrode board between a plurality of piezo-electric boards wherein an electrode layer is formed in both surfaces thereof, adding a glass element to an electrode layer and making surface roughness of an electrode layer not exceeding a specified value. SOLUTION: A piezo-electric ceramic material which is mainly composed of lead titanate zirconate is used for a piezo-electric board 1. A plurality of piezo-electric boards 1 are stacked and an electrode board 3 is interposed between the piezo-electric boards 1 through an electrode layer 2. The electrode layer 2 consists of glass elements such as Ag and PbO-SiO2 -B2 O3 and is formed about 3 to 30μm thick. The electrode layer 2 is formed so that its surface roughness is at most 2μm when baking to the piezo-electric board 1 is finished. That is, the electrode board 3 is interposed between a plurality of piezo-electric boards 1 and load applied to a multilayer body 10 is made uniform to the utmost when the electrode layer 2 is melted while it is pressurized and heated to be joined to the electrode board 3.