Study on the Pressureless Sintering and Properties of (K_0.5Na_0.5)_1-xLi_xNb_1-yTa_yO₃ Lead-Free Piezoelectric Ceramics

Abstract:

Potassium sodium niobate ((K_0.5Na_0.5)_1-xLi_xNb_1-yTa_yO₃) powers were prepared by solid phase synthesis and (K_0.5Na_0.5)_1-xNb_1-yTa_yO₃ lead-free piezoelectric ceramics were fabricated by the pressuerless sintering. The relationship among the powder phase composition and electric properties was studied. The results show that when x=0.5, the sintering temperature is 1050°C,and the polarization voltage is 3 kV/mm, the (K_0.5Na_0.5)_1-xLi_xNb_1-yTa_yO₃ piezoelectric ceramics with the better piezoelectric properties are prepared. (The relative density is 94%, the piezoelectric constant d₃₃=105pC/N, the planar electro-mechanical coupling coefficient k_p=0.39, the medium loss tanδ=0.29, the mechanical quality factor Q_m=45, and the dielectric constant ε_r=720). As the increase of the polarization votage, the ceramic piezoelectric properties are increased. When the polarization voltage E=3kV/mm, the polarization tends to be saturation on the whole.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1403-1407
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1403
• Online since: June 2012
• Authors: Hang Fei Hao, G.Q. Tan, Peng Xiong, Bo Qin, Hui Jun Ren
• Keywords: (K_0.5Na_0.5)_1-xLi_xNb_1-yTa_yO₃, Pressureless Sintering, Solid Phase Synthesis

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