Origin of high mechanical quality factor in CuO-doped (K, Na)NbO₃-based ceramics

Abstract

The origin of a high mechanical quality in CuO-doped (K, Na)NbO₃-based ceramics is addressed by considering the correlations between the lattice positions of Cu ions and the hardening effect in K_0.48Na_0.52+xNbO₃--0.01CuO ceramics. The Cu ions simultaneously occupy K/Na and Nb sites of these ceramics with x = 0 and 0.02, only occupy the K/Na site of the ceramics with x = --0.02, and mostly form a secondary phase of the ceramics with x = --0.05. The Cu ions lead to the hardening of ceramics with an increase of E_C and Q_m by only occupying the K/Na site, together with the formation of double hysteresis loops in un-poled compositions. A defect model is proposed to illuminate the origin of a high Q_m value, that is, the domain stabilization is dominated by the content of relatively mobile O^2-- ions in the ceramics, which has a weak bonding with Cu_K/Na defects.

Keywords

lead-free piezoelectric ceramic / (K, Na)NbO₃ (KNN) / mechanism of hardening effect / mechanical quality factor Q_m / domain stabilization

References

[1] Gerthsen P, Härdtl K H, Schmidt N A. Correlation of mechanical and electrical losses in ferroelectric ceramics. Journal of Applied Physics, 1980, 51(2): 1131

[2] Uchino K, Zheng J H, Chen Y H, . Loss mechanisms and high power piezoelectrics. Journal of Materials Science, 2006, 41(1): 217-228

[3] Zhang S, Xia R, Shrout T R. Lead-free piezoelectric ceramics vs PZT? Journal of Electroceramics, 2007, 19(4): 251-257

[4] Rödel J, Jo W, Seifert K T P, . Perspective on the development of lead-free piezoceramics. Journal of the American Ceramic Society, 2009, 92(6): 1153-1177

[5] Xiao D Q, Wu J G, Wu L, . Investigation on the composition design and properties study of perovskite lead-free piezoelectric ceramics. Journal of Materials Science, 2009, 44(19): 5408-5419

[6] Shrout T R, Zhang S J. Lead-free piezoelectric ceramics: Alternatives for PZT? Journal of Electroceramics, 2007, 19(1): 113-126

[7] Härdtl K H. Electrical and mechanical losses in ferroelectric ceramics. Ceramics International, 1982, 8(4): 121-127

[8] Lin D, Kwok K W, Chan H L W. Double hysteresis loop in Cu-doped K_0.5Na_0.5NbO₃ lead-free piezoelectric ceramics. Applied Physics Letters, 2007, 90(23): 232903 (3 pages)

[9] Gao Y, Uchino K, Viehland D. Effects of thermal and electrical histories on hard piezoelectrics: A comparison of internal dipolar fields and external dc bias. Journal of Applied Physics, 2007, 101(5): 054109 (6 pages)

[10] Lin D, Kwok K W, Wong Lai-wa Chan H.Double hysteresis loop and aging effect in K_0.5Na_0.5NbO₃–K_5.4Cu_1.3Ta₁₀O₉ lead-free ceramics. Journal of the American Ceramic Society, 2009, 92(6): 1362-1365

[11] Carl K, Hardtl K H. Electrical after-effects in Pb(Ti, Zr)O₃ ceramics. Ferroelectrics, 1977, 17(1): 473-486

[12] Ren X. Large electric-field-induced strain in ferroelectric crystals by point-defect-mediated reversible domain switching. Nature Materials, 2004, 3(2): 91-94

[13] Zhang L, Ren X. Aging behavior in single-domain Mn-doped BaTiO₃ crystals: Implication for a unified microscopic explanation of ferroelectric aging. Physical Review B: Condensed Matter and Materials Physics, 2006, 73: 094121

[14] Tan Q, Li J, Viehland D. Role of lower valent substituent-oxygen vacancy complexes in polarization pinning in potassium-modified lead zirconate titanate. Applied Physics Letters, 1999, 75(3): 418-420

[15] Zhang Y, Li J, Fang D. Oxygen-vacancy-induced memory effect and large recoverable strain in a barium titanate single crystal. Physical Review B: Condensed Matter and Materials Physics, 2010, 82: 064103

[16] Takao H, Saito Y, Aoki Y, . Microstructural evolution of crystalline-oriented (K_0.5Na_0.5)NbO₃ piezoelectric ceramics with a sintering aid of CuO. Journal of the American Ceramic Society, 2006, 89(6): 1951-1956

[17] Wang H-Q, Dai Y-J, Zhang X-W. Microstructure and hardening mechanism of K_0.5Na_0.5NbO₃ lead-free ceramics with CuO doping sintered in different atmospheres. Journal of the American Ceramic Society, 2012, 95(4): 1182-1184

[18] Park H-Y, Seo I-T, Choi M-K, . Microstructure and piezoelectric properties of the CuO-added (Na_0.5K_0.5)(Nb_0.97Sb_0.03)O₃ lead-free piezoelectric ceramics. Journal of Applied Physics, 2008, 104(3): 034103 (7 pages)

[19] Su S, Zuo R, Wang X, . Sintering, microstructure and piezoelectric properties of CuO and SnO₂ co-modified sodium potassium niobate ceramics. Materials Research Bulletin, 2010, 45(2): 124-128

[20] Park B C, Hong I K, Jang H D, . Highly enhanced mechanical quality factor in lead-free (K_0.5Na_0.5) NbO₃ piezoelectric ceramics by co-doping with K_5.4Cu_1.3Ta₁₀O₂₉ and CuO. Materials Letters, 2010, 64(14): 1577-1579

[21] Li E, Kakemoto H, Wada S, . Enhancement of Q_m by co-doping of Li and Cu to potassium sodium niobate lead-free ceramics. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2008, 55(5): 980-987

[22] Park H Y, Seo I T, Choi J H, . Low-temperature sintering and piezoelectric properties of (Na_0.5K_0.5)NbO₃ lead-free piezoelectric ceramics. Journal of the American Ceramic Society, 2010, 93(1): 36-39

[23] Alkoy E M, Papila M. Microstructural features and electrical properties of copper oxide added potassium sodium niobate ceramics. Ceramics International, 2010, 36(6): 1921-1927

[24] Lin D, Kwok K W, Chan H L W. Piezoelectric properties and hardening behavior of K_5.4Cu_1.3Ta₁₀O₂₉-doped K_0.5Na_0.5NbO₃ ceramics. Journal of Applied Physics, 2008, 103(6): 064105 (5 pages)

[25] Lim J B, Zhang S, Lee H J, . Shear-mode piezoelectric properties of modified-(K,Na)NbO₃ ceramics for “hard” lead-free materials. Journal of the American Ceramic Society, 2010, 93(9): 2519-2521

[26] Lv Y G, Wang C L, Zhang J L, . Modified (K₀.5Na₀.5)(Nb₀.9Ta₀.1)O₃ ceramics with high Q_m. Materials Letters, 2008, 62(19): 3425-3427

[27] Matsubara M, Yamaguchi T, Sakamoto W, . Processing and piezoelectric properties of lead-free (K,Na)(Nb,Ta)O₃ ceramics. Journal of the American Ceramic Society, 2005, 88(5): 1190-1196

[28] Yang M-R, Tsai C-C, Hong C-S, . Piezoelectric and ferroelectric properties of CN-doped K_0.5Na_0.5NbO₃ lead-free ceramics. Journal of Applied Physics, 2010, 108(9): 094103 (5 pages)

[29] Körbel S, Marton P, Elsässer C. Formation of vacancies and copper substitutionals in potassium sodium niobate under various processing conditions. Physical Review B: Condensed Matter and Materials<?Pub Caret?> Physics, 2010, 81: 174115

[30] Shigemi A, Wada T. Evaluations of phases and vacancy formation energies in KNbO₃ by first-principles calculation. Japanese Journal of Applied Physics, 2005, 44(11): 8048-8054

[31] Zhen Y, Li J F. Abnormal grain growth and new core–shell structure in (K,Na)NbO₃-based lead-free piezoelectric ceramics. Journal of the American Ceramic Society, 2007, 90(11): 3496-3502

[32] Zuo R, Ye C, Fang X, . Processing and piezoelectric properties of (Na_0.5K_0.5)_0.96Li_0.04(Ta_0.1Nb_0.9)_1-xCu_xO_3-3x/2 lead-free ceramics. Journal of the American Ceramic Society, 2008, 91(3): 914-917

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag Berlin Heidelberg