• Electrical & Electronic Materials
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• v.9 no.6
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• pp.551-557
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• 1996

To decrease the hysteresis of electric field induced strain, $Y_{2}$ $O_{3}$ dopant of which amount is 0-0.8wt% was added to the (P $b_{0.73}$B $a_{0.27}$)(Z $r_{0}$ 75/ $Ti_{0.25}$) $O_{3}$ ceramics. Electromechanical coupling coefficients of the specimen with 0.1 Wt% $Y_{2}$ $O_{3}$ were $k_{p}$=26.9% and $k_{31}$ =20.4%, which exhibited the maximum value at the constant bias electric field of 10 kV/cm. At the same $Y_{2}$ $O_{3}$ addition amount, electric field piezoelectric constant ( $d_{3l}$) and strain(.DELTA.l/l) showed the maximum values of 139.6*10$^{-12}$ [C/N] and 126*10$^{-6}$ .DELTA. l/l respectively at 10 kV/cm electric field. And the hysteresis of strain showed the minimum value of 17.5%. So, we propose that it is possible to apply PBZT system with $Y_{2}$ $O_{3}$ dopant to the electrostrictive actuator.r.r.

• Electrical & Electronic Materials
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• v.10 no.9
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• pp.909-915
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• 1997

To improve the electro-induced strain and to decease the hysteresis of that W $O_3$dopant of which amount is 0~0.8wt% was added to (P $b_{0.73}$/B $a_{0.27}$)(Z $r_{0.75}$/ $Ti_{0.25}$) $O_3$+0.1wt% $Y_{2}$/ $O_3$ceramics. At the specimen with 0.4 wt% W $O_3$the electromechanical coupling coefficient( $K_{31}$ ) showed the maximum value of 23.6% at D.C 10 kV/cm electric field. At the same W $O_3$addition amount the piezoelectric constant( $d_{31}$ ) and the electro-induced strain($\Delta$$\ell$/$\ell$)showed the highest values of 182$\times$10$^{-12}$ [C/N] 210$\times$10$^{-6}$ $\Delta$$\ell$/$\ell$at D.C. 10 kV/cm electric field. respectively0 kV/cm electric field. respectivelyvely.

• Electrical & Electronic Materials
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• v.10 no.5
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• pp.434-439
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• 1997

It this paper, the piezoelectric and electro-induced strain properties of (P $b_{1-}$2x/3/B $i_{x}$ )[N $i_{1}$3/N $b_{2}$3/)$_{0.4}$( $Ti_{0.6}$Z $r_{0.4}$)$_{0.6}$] $O_3$ceramics (x=0, 0.005, 0.02) were investigated with the substitution of B $i^{3+}$, and the feasibility of the application for bimorph actuator was evaluated by measuring the dynamic properties of the piezoelectric bimorph fabricated with above ceramics. Dielectric constant was enhanced with the increase of B $i^{3+}$ substitution, and appeared the maximum value of 5032 at x=0.01 composition. Increasing the substitution of B $i^{3+}$, the electromechanical coefficient( $k_{p}$ , $k_{31}$ ) was increased up to the substitution of 0.5 mol% B $i^{3+}$, showed the value of 0.656, 0.439, respectively. The piezoelectric constant( $d_{33}$ $d_{31}$ ) had the highest value of 344, 825 with the substitution of 0.5 mol% B $i^{3+}$. The strain, generated by 60 Hz AC electric field, had the largest value of 1200($\times$10$^{-6}$ $\Delta$1/1) in the composition with the substitution of 0.5 mol% B $i^{3+}$. The dynamic properties of the bimorph actuator, fabricated with the composition substitution of 0.5 mol% B $i^{3+}$, showed the largest value of 325 $\mu$m at $\pm$150 V square pulse. square pulse.are pulse..