| 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 lead-free piezoelectric ceramics were prepared by the traditional ceramic process, and the impact of preparation technology, especially the sintering temperature on ceramic structure and performance of 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 lead-free piezoelectric ceramics was discussed. XRD analysis results showed that ceramics were perovskite structure. Ceramics were tetragonal phase when the sintering temperature is 1060℃, but ceramics transformed orthorhombic and tetragonal phases coexistence when the sintering temperature is 1070 1090℃. Microscopic morphology analysis shows ceramics grain gradually increased with the increase of sintering temperature. When the sintering temperature is 1080℃, ceramic has the optimal microscopic morphology:grain size is relative uniform, and average particle size is about 10μm. The study also found that Curie temperature Tc of ceramics were increasing with the increase of sintering temperature, and after peaked at 494℃ when 1080℃ Tc began to reduce. But piezoelectric constant d33 and plane electromechanical coupling coefficient Kp and thickness electromechanical coupling factor Kt had been rising firstly, and dielectric loss tanδ had been reducing. When the sintering temperature is 1080℃, ceramics showed the best electrical performance, d33 for 208pC/N, Kp for 0.39, Kt for 0.36, tanδ for 0.019. And the further increase of sintering temperature, the electrical properties of the ceramics reduced.The impact of the K/Na ratio change on the structure and properties of 0.94(KxNa1-x)NbO3-0.06LiNbO3 lead-free piezoelectric ceramics was researched. XRD analysis results showed that ceramics were perovskite structure at 0.40≤x≤0.60, and its compositions were orthorhombic symmetry and tetragonal symmetry coexistence. With the increase of x, tetragonal phases composition was weakening, while orthorhombic composition enhancing. Microscopic morphology analysis shows the ceramic grain size firstly increased with the increase of x. The grain is the largest when x=0.50, and grain size decreased after x increase. With the increase of x, Curie temperature Tc of ceramics moved to high temperature, focused between 465494℃. But piezoelectric constant d33 and plane electromechanical coupling coefficient Kp and thickness electromechanical coupling factor Kt are firstly increased then decreased. When x=0.45, ceramics had the optimal piezoelectric properties, and d33, Kp and Kt, for 235pC/N, 0.42 and 0.39 respectively.The influence of add excessive Na on the structure and properties of 0.94(K0.5Na0.5+xNbO3)-0.06LiNbO3 ceramics was studied. XRD analysis results showed that ceramics were perovskite structure with the scope of the study（0≤x≤0.02）, and its compositions were orthorhombic and tetragonal phases coexistence. With the increase of x, tetragonal phases composition was weakening, while orthorhombic composition enhancing. Microscopic morphology analysis shows the ceramic grain size firstly increased then decreased with the increase of x. With the increase of x, Curie temperature Tc of ceramics moved to the low temperature, focused between 477477℃. And ceramic piezoelectric constant d33, plane electromechanical coupling coefficient Kp, thickness electromechanical coupling coefficient Kt and the relative dielectric constant εr increases gradually. When x=0.010, ceramic has the best electrical performance, d33 for 255pC/N,Kp for 0.46,Kt for 0.42 and εr for 850. But with the further increase of x, electrical properties of the ceramic began to decrease.The effects of add the sintering additives ZnO on the structure and properties of 0.94(K0.5Na0.5)NbO3-0.06LiNbO3-x ZnO ceramics was studied. XRD analysis results showed that ceramics were perovskite structure in the range of doping with the quality percentage（0≤x≤0.01）. When x≤0.005, ceramics were orthorhombic and tetragonal phases coexistence, and when x≥0.0075, ceramics transformed a single orthorhombic phase. Microscopic morphology analysis shows with increasing x, the ceramic grain size decreased then increased. With the increase of x, orthogonal-tetragonal phase transition temperature To-t of the ceramics moved to high temperature, and Curie temperature Tc moved to low temperature, focused between 470470℃. And piezoelectric constant d33, plane electromechanical coupling coefficient Kp and thickness electromechanical coupling factor Kt were reducing. After adding ZnO, ceramic has the best electrical performance, when x=0.005, d33, Kp and Kt, for 194pC/N, 0.31 and 0.30 respectively.
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