| Summary: | 碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 91 === The present study investigates the characteristics of the interface between the electrode material and ceramic dielectric. Ceramic dielectric was made from commercial available BaTiO3. Silver paste is used as the electrode material. BaTiO3 had been formed and sintered (1290℃/2h) to obtain the disc with a hole in the central part. The silver film was prepared by screen-printing silver paste onto the disc. After the sintering at 600℃ for 1h, the silver film adheres to the disc and binder in the paste is burnt away.
The adhesion strength has been determined by means of Bulge and Blister test. During the first step of the experiment, a free-standing film membrane is pressurized by liquid injection through a hole in the substrate. This is reported as an increasing curve in pressure p vs. membrane deflection h coordinates. When the film starts debonding, the outline of the membrane changes from its initial shape and its volume increases rapidly, thus causing a decrease of the fluid pressure and a visible change of regime on the p vs. h curve. When the debonding is controlled, theoretical considerations show that the p vs. h curve should follow a decreasing hyperbolic law: Gi=C . p . h
where C is a numerical dimensionless constant which varies slightly between 0.618 and 0.516 according to the residual stress value in the film and Gi is the interfacial crack propagation energy.
The elastic properties of porous silver membrane are determined by bulge test, and the interfacial crack propagation energy is measured by Blister test in this study.
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