Cerium Oxide 첨가에 따른 압전트랜스포머용 $Pb(Mn_{1/3}Nb_{2/3})O_3-Pb(Zr,Ti)O_3$ 세라믹의 압전특성

Piezoelectric Characteristics of Pb(Mnsub 1/3Nb 23)Osub 3-Pb(Zr, Ti)Osub 3 Ceramics with $CeO_2$ Impurity for the Piezoelectric Transformer

Piezoelectric properties of PMN-PZT ceramics with $CeO_2$ impurity were investigated. Mechanical quality factor, $Q_m$ of 1792, 1285 and the electromechanical coupling coefficient, $k_p$ of 0.52, 0.54 were obtained from the specimen with 0.25 and 0.5 mole % $CeO_2$ respectively. Curie temperature was decreased with the addition of $CeO_2$ while the electric coercive field was proportional to the amount of impurity. Based on the system ceramics with 0.5 mole % cerium oxide, a Rosen type piezoelectric transformer was fabricated and tested. Voltage step-up ratios of 230 and 13 were obtained from the transformer at no load and $100 k\Omega$ resistance, respectively. Experimental results showed a potential of the transformer for the practical use coupled with the expected strength increase by the grain size refinement.