Densification Behavior and Electrical Properties of K₃Li₂(Nb_{1 - x}Ta_x)₅O₁₅ Ceramics

Abstract

Tetragonal tungsten bronze structured K₃Li₂(Nb_{1 - x}Ta_x)₅O₁₅(KLNT) (0.0≤x≤1.0) ceramics was synthesized by the solid state reaction method. The sintering behavior, phase development and dielectric characteristics of KLNT ceramics as a function of x (Nb/Ta ratio) were examined. When the content of Ta increased the temperature where the highest sintered density obtained increased. More Ta increased the degree of ionic character in the KLNT ceramics which enabled a formation of KLT single phase, even though KLN single phase was not obtained. On the basis of dielectric analysis and lattice parameter it was found that a morphotropic phase boundary (MPB) region exists around x = 0.4.

Keywords:

• Tungsten bronze structure
• KLN
• KLT
• ferroelectric
• morphotropic phase boundary

Acknowledgement

This work was supported by Grant No.R01-2003-000-11606-0 from the Basic Research Program of the Korea Science & Engineering Foundation.