Abstract: A method of making a transducer which has a head mass, a tail mass and a plurality of piezoelectric rings arranged in a stack with alternate electrodes, which are to be glued to the piezoelectric rings. The electrodes are of the type which have a surface on either side defining passageways when abutting an adjacent component. The components are assembled without the use of adhesive and then placed into a vacuum chamber where the pressure is reduced. The pressure is then brought back to normal atmospheric pressure in the presence of an adhesive surrounding the stack, with the adhesive being drawn into the passageways and toward the interior of the stack as a result of the pressure differential created. The adhesive joins the components together and also coats the outside of the stack so that after curing it functions as an anti-arcing coating.

Abstract: A moisture absorbing, anti-arcing compound comprises a mixture of a moist active isocyanate resin and a generic anti-arcing compound. The isocyanate resin reacts with residual moisture in a high voltage ceramic insulator, thus tying it up chemically. This prevents diffusion of the moisture into the anti-arcing compound and resultant degradation. The compound according to this invention is especially useful for ceramics which may not be baked dry at elevated temperatures.