超音波換能器之研製

Abstract

本文將探討以壓電片PZT-5J和鋁鑄件組成製作防滴型超音波壓電陶瓷換能 器的方法及性能檢測分析。其中包括陶瓷片的選擇，以及黏貼等製程技術 技術，以及聲(電)性量測技，術結果都作一詳細的探討。高機電耦合係數 的陶瓷材料可提高換能器的效率，本實驗中則控制鋁鑄件貼合面的厚度， 由0.35增至1.89mm，來控制換能器的使用頻率。應證 bending mode方程 式，並對實驗中的真實情形做一些適當的修正，最後完成一對適合在50 KHz工作的換能器。利用hp4194及hp35665A來測量換能器的聲音及電氣方 面的特質，來驗證換能器的品質. In this research , the fabrication techniques of ultrasonic transducers were systematically studied ; the performance and acoustic properties of the transducers were tested and analyzed. The transducers are composed of an active piezoelectric ceramicdisc and die-casted aluminum hell on which the disc is attached. The central frequency of the transducers were intentionally varied by controlling the thickness of aluminum shell from 0.35 to 1.89 mm . The correlation between the central frequency and thickness was established and confirmed by the bending mode equation although a slight modification for the equation was needed. The fabrication processing was optimized and the resultant quality of the transducers were measured and reported in this thesis.