Dependence of Strength and Crack Growth of PZT Ceramics on Poling Strength

Poling 강도 변화에 따르는 PZT 세라믹스의 강도와 균열성장 의존성

  • 이홍림 (연세대학교 세라믹공학과) ;
  • 권종오 (연세대학교 세라믹공학과) ;
  • 한봉석 (연세대학교 세라믹공학과)
  • Published : 1997.08.01

Abstract

The dependence of strength, crack growth, fracture mode and degree of domain rearrangement of PZT ceramics on poling strength were studied. The PZT [(Pb0.94Sr0.06)(Zr0.46Ti0.54)O3+Nb(trace)] specimens were poled at 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 kv/mm, and the strength of the specimens was measured by 3 point flexure system. The bending strength of the specimen decreased in different modes according to the bending directions; xz, zx and yz plane direction with x axis of the poling direction in Cartesian coordinate system. The strength differences between the directions increased as the poling strength increased. The fracture mode transferred to intergranular fracture mode from transgranular one as the poling strength increased. The mechanical breakdown occurred when the poling strength higher than 3 kV/mm was applied to the specimen. It was observed that the crack length increased in the normal direction to the poling direction, however, decreased in the parallel direction to the poling direction when the poled PZT specimen was indented by the Vickers indenter. However, the crack produced by indentation continuously was continuously increased little by little after indentation on the specimen. The domain rearrangement occurred as the poling strength increased and the domains were rearranged more effectively when the electric field was continuously increased little by little.

Keywords

References

  1. Ferroelectric Materials and Their Application Yuhuan Xu
  2. Fundamentals of Piezoelectricity Takuro Ikeda
  3. Am. Ceram. Soc. Bulletin v.63 no.9 Mechanical Behavior of Ferroelectric Ceramics Kiyoshi Okazaki
  4. J. Am. Ceram. Soc. v.68 no.5 Anisotropy of Francture Toughness of Piezoelectric Ceramics G. G. Pisarenko;V. M. Chushko;S. P. Kovalev
  5. J. Am. Ceram. Soc. v.73 no.3 Fracture Mechanisms in Ferroelectric -Ferroelastic Lead Zirconate Titanate (ZrTi=0.64:0.46) Ceramics Karun Metha; Anil V. Virkar
  6. Private communication with the powder supplier
  7. Ferroelectrics v.81 Poling Process, Microcracks and Mechanical Quality of PZT Ceramics Karel Nejczchleb;Frantisek Kroupa;Miroslav Boudys;Jiri zelenka
  8. Ferroelectrics v.50 Fracture of Piezoelectric Ceramics R. F. Cook;S.W Freiman;B. R. Lawn;R. C. Pohanka
  9. J. Am. Ceram. Soc. v.77 no.7 Hengchu Cao;Anthony G. Evans
  10. J. Am. Ceram. Soc. v.73 no.1 Effect of Grain Size on the Fracture Mode of Lead Zircornate Titanate Ceramics Sang-Beom Kim;Doh-Yeon Kim;Jeong-Joo Kim;Sang-Hee Cho
  11. 제8회 요업기술원발표논문집 PZT계 압전세라믹스의 분극특성에 관한 연구 김병익