Effect of sintering time on reactive templated grain growth and electromechanical properties of NKLNT ceramics

The effects of sintering time on (Na0.51K0.47Li0.02)(Nb0.8Ta0.2)O-3, a textured piezoelectric ceramic, in terms of its electromechanical properties were investigated. Grain growth and enhanced electromechanical properties were manifested in specimens prepared via solid state reaction method up to 1 hour of sintering time. These characteristics were enhanced slightly further and were maintained at comparable values in specimens sintered for 10 hours with a piezoelectric coefficient d(33) similar to 194 pC/N. The characteristics diminished drastically in specimens sintered for 20 hours. Degree of orientation substantially increased, in case of textured specimens manufactured by reactive template grain growth method, according to sintering time and consequently, their electromechanical properties continued to increase greatly up to 10 hours of sintering time with a d(33) similar to 271 pC/N. Degree of orientation increased much more in specimens sintered for 20 hours, whereas their electromechanical properties decreased slightly with a d(33) similar to 238 pC/N. The results indicate that sintering time has an effect on the degree of orientation and electromechanical properties of the textured piezoelectric ceramics.