Preparation of Piled Ba(ZrxTi1-x)O3 with Flat Temperature Dependence in Dielectric Constant

In order to obtain the material having a flat temperature dependence in dielectric constant, Ba(ZrxTi1-x)O3 powder compacts with different compositions were piled and sintered under HIP pressure and atmospheric pressure. The Ba(ZrxTi1-x)O3 obtained under 200 MPa of HIP pressure revealed the flat temperature dependence of dielectric constant being 3800 over the temperature range of 5∼52°C. Although this material had excellent flatness in temperature dependence, this dielectric constant was lower than that expected. This seemed to be due to the residual stress caused by HIP pressure. The piled Ba(ZrxTi1-x)O3 was also obtained under atmospheric pressure by calcining the starting powder mixtures sufficiently. This material revealed a higher dielectric constant of 5000 over the temperature range of 16∼30°C. However, this temperature dependence curve showed 5 peaks corresponding to five compositions. The dielectric material having excellent flat temperature dependence, which showed 8200 of dielectric constant over the temperature range of −1∼26°C, was obtained by using nine different compositions and by controlling the amounts of the powders. In addition, dielectric constant 5900 was obtained over the temperature range of 0∼45°C by atmospheric sintering of the Hiped Ba(ZrxTi1-x)O3.