The Research Of Sodium Niobate-based Piezoelectric Ceramics And The Textured Processing

This paper have introduced the status of the research on the lead free piezoelectric ceramics, and interpreted the sodium niobate lead-free piezoelectric ceramics from three aspects: firstly, potassium sodium niobate lead-free piezoelectric ceramics suitable for practical use were fabricated;The influence of the addition of SrTiO₃, BaTiO₃, V₂O₅, La₂O₃ and many sorts of thulium on the material of (K_0.44Na_0.52Li_0.04) (Nb_0.84Ta_0.10Sb_0.06) O₃ has been discussed;What's more, the influence of temperature and dwell time on this kind of material also has been discussed. Secondly, the plate-like NaNbO₃ templates have been synthesized by two step molten salt synthesis (MSS) process. In the first step MSS process, the plate-like Bi_2.5Na_3.5Nb₅O₁₈(BiNN5 )particles were fabricated;In the second step MSS process, using the BiNN5 as the processor, the plate-like NaNbO₃ templates could be synthesized. This paper paid more attention to discusse the influence of temperature, dwell time and the amount of salt on the properties of BiNN5 and NaNbO₃ templates. Thirdly, the fabrication of textured potassium sodium niobate lead-free piezoelectric ceramics using RTGG method has also been discussed in this paper. The influence of different templates and different dwell time on the properties of textured potassium sodium niobate lead-free piezoelectric ceramics have been discussed. As for the conventional solid synthesis, the result shows that the addition of SrTiO₃ can increases the piezoelectric and dielectric properties. The doping of BaTiO₃ has little impact on this kind of material. The doping of V₂O₅ and La₂O₃ will impair the piezoelectric properties. As far as the fabrication of template is concerned, the result shows that the samples fabricated at 1130℃ for 3 h as for BiNN5 and the samples fabricated at 950℃ for 6 as for NaNbO₃ preserves better properties. As for the textured potassium sodium niobate lead-free piezoelectric ceramics, the result shows that the piezoelectric properties of this kind of material increases much after being textured.