An improved sandwich dipole transducer for high temperature environment

The basic structure of the traditional sandwich dipole transducers consists of a metal plate or support slice adhering to two piezoelectric ceramic slices in each side. Due to the apparent difference between thermal expansion coefficients of two kinds of material, the traditional dipole transducer always encounters a technical difficulty that its adhesive layer becomes very weak in the high-temperature environment and piezoelectric ceramic slices might detach from the support slice. Aim at this difficulty; we present a novel scheme by cutting notches at the midline of the piezoelectric ceramic slices. As the piezoelectric ceramic slices are cut into small pieces, shear stress at the adhesive layer releases drastically and the piezoelectric ceramic slices would be stuck on the support slice tightly. Numerical simulations with a finite element method are conducted for evaluating the efficiency of the modified dipole transducer. Since the notched sandwich dipole transducer releases the shear stress in the adhesive layer, this improved design would enhance stable conditions of the dipole transducer for the high-temperature environment.