The Characteristics of Piezoelectric Strian Constants on PNN-PZ-PT Ceramics

,; ,; ,; ,; ,; ,

J. Korean Ceram. Soc. > Volume 26(6); 1989 > Article

Journal of the Korean Ceramic Society 1989;26(6): 802.

PNN-PZ-PT계 세라믹스의 압전변위특성

정수태, 남효덕¹, 조상희²

부산공업대학 전자공학과
¹영남대학교 전자공학과
²경북대학교 재료공학과

The Characteristics of Piezoelectric Strian Constants on PNN-PZ-PT Ceramics

ABSTRACT

The temperature dependence of piezoelectric strain constant and the electric field induced strain are investigated as a function of PT in 0.5[xPT-(1-x)PZ]-0.5PNN ceramics. The piezoelectric strain constant d31 has the highest value(360$times$10-12m/V) at PT=0.68. The temperature dependence of d31 is improved as Curie temperature of sample is increased, and the electric field dependence of induced strain is decreased with the coercive field increased. This ceramic system shows both piezoelectric effect and electrostrictive effect under the applied electric field. The piezoelectric of tetragonal phase is higher than that of rhombohedral phase, and the magnitude of electrostrictive constant is appeared in the order of morphotropic, rhombohedral and tetragonal phase. The piezoelectric strain constant with applied field must be considered theelectrostrictive effect due to 90$^{circ}$domain wall displacements, and the displacement of bimorph type actuator agrees with the calulated value well.