Fabrication of Dense KNbO3 Ceramics Derived from KHCO3 as a Starting Material

Potassium niobate-based ceramics, K(1+x)NbO3 (KN-10000x, x = 0–0.001), were fabricated using KHCO3 powder as a starting material to improve their reproducibility. The KN-7.2 ceramics all had high relative density ratios exceeding 96% and resistivities of above 1012 Ω·cm. Additionally, many KN-7.2 ceramics were prepared under different levels of humidity of about ∼70% in the weighing process. The relative density ratios of all the KN-7.2 ceramics were similar, showing the excellent reproducibility obtained using KHCO3 powder as a starting material. The electromechanical coupling factor k33 and piezoelectric strain constant d33 of the KN-7.2 ceramics were 0.50 and 90 pC/N, respectively.

[1]  X. Ni,et al.  Fire suppressing performance of superfine potassium bicarbonate powder , 2011 .

[2]  T. Wada,et al.  Synthetic Mechanism of Perovskite-Type KNbO3 by Modified Solid-State Reaction Process , 2011 .

[3]  K. Kakimoto,et al.  Synthesis of KNbO3 Piezoelectric Ceramics Using Citrate Precursors , 2008 .

[4]  Kenji Matsumoto,et al.  Fabrication and Electrical Properties of Potassium Niobate Ferroelectric Ceramics , 2007 .

[5]  T. Wada,et al.  Fabrication of Lead-Free Piezoelectric KNbO3 Ceramics by Modified Solid State Reaction Method , 2006 .

[6]  Kenji Matsumoto,et al.  Piezoelectric Properties of Pure and Mn-doped Potassium Niobate Ferroelectric Ceramics , 2006 .

[7]  N. Setter,et al.  Preparation and Characterization of KNbO3 Ceramics , 2005 .

[8]  K. Kakimoto,et al.  Solid-Solution Structure and Piezoelectric Property of KNbO3 Ceramics Doped with Small Amounts of Elements , 2004 .

[9]  J. Speight,et al.  Perry's Standard Tables and Formulas for Chemical Engineers , 2003 .

[10]  S. Tashiro,et al.  Sinterability and Piezoelectric Properties of KNbO3 Ceramics after Substituting Pb and Na for K , 2002 .

[11]  T. Tokiwa,et al.  Domain structures in KNbO3 crystals and their piezoelectric properties , 2002 .

[12]  S. Wada,et al.  Poling Treatment and Piezoelectric Properties of Potassium Niobate Ferroelectric Single Crystals , 2001 .

[13]  Haruhiko Tanaka Comparison of thermal properties and kinetics of decompositions of NaHCO3 and KHCO3 , 1987 .

[14]  R. E. Jaeger,et al.  Hot Pressing of Potassium‐Sodium Niobates , 1962 .