The relations of sintering conditions and microstructures of [Bi0.5(Na1-x-yKxLiy)0.5]TiO3 piezoelectric ceramics

Bismuth sodium titanate (abbreviated as BNT) based solid solution, [Bi-0.5(Na1-x-yKxLiy)(0.5)]TiO3 (0<x+y>1) ceramics, was invented in our group. These ceramics, which are considered as new candidates for lead-free piezoelectric materials, were prepared by conventional ceramic sintering technique. The results of X-ray diffraction show that the ceramics possess a single perovskite phase. The relations of the sintering conditions and the microstructures of the ceramics were studied. It was found that the optimized sintering condition is at 1100-1150degreesC for 2-3h, the grains of the ceramics have very regular shape, and the grain size of the ceramics is in the range of 1.3-2.2mum. These ceramics with the compositions of high amount of K+ and low amount of Li+ have relatively large piezoelectric charge constant (d(33)), and can be put into practical applications. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.