Field-induced recoverable strain behavior of CuO-added K 0.5Na0.5NbO3 ceramics and 1-3 fiber/epoxy piezocomposites
Journal of Applied Physics, cilt.108, sa.9, 2010 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 108 Sayı: 9
- Basım Tarihi: 2010
- Doi Numarası: 10.1063/1.3503845
- Dergi Adı: Journal of Applied Physics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Maltepe Üniversitesi Adresli: Evet
Özet
Lead-free, dense, 1 mol % CuO-added potassium sodium niobate K 0.5Na0.5NbO3 (KNN) fibers were successfully drawn using a novel alginate gelation technique. Piezocomposites with 1-3 connectivity were prepared with an epoxy matrix with various fiber volume fractions (Vf). Electrical properties of the piezocomposites were investigated and compared with bulk KNN ceramics of the same composition. The dielectric constant of the piezocomposites were found to increase from 67 to 191 with the addition of CuO into KNN and increasing Vf in the piezocomposite. A constricted, antiferroelectriclike double hysteresis polarization versus electric field (P-E) loop was observed in bulk KNN. A large and fully recoverable electrostrain of 0.07% was measured for bulk KNN and 0.03% for the piezocomposites under an electric field of 50 kV/cm, respectively. The double hysteresis P-E loop and the recoverable nature of the electrostrain was due to the Cu Nb-VO defect dipoles creating an internal field that restores the original domain pattern when the field is removed. A very high electrostrictive Q33 coefficient of 35.6× 10-3 m4 / C2 and an even higher Q33 of 162× 10 -3 m4 / C2 was obtained for bulk KNN and piezocomposites, respectively. © 2010 American Institute of Physics.