Investigation Of BCZT Lead Free Piezoelectric Ceramics' Doping Modification And Poling Conditions

In the recent years, with the continuously development of society and the ceaselessly advancement of industry, people pay more and more attention on environment issues. Particularly, in the realm of piezoelectric materials. As a result, the environment harmless lead-free piezoelectric materials substitute the Pb-based piezoelectric materials has become an urgent task for researchers. So our work is based on BCZT-based piezoelectric material. And we obtained outstanding properties through different ways.Because of the low curie temperature of BCZT, which around 90?. Firstly in order to improve the curie temperature we adjust Zr/Ti, including two different ratios: 7/93?5/95. And then achieve the optimal properties through changing the content of Ca.Next, on the base of Zr/Ti=5/95 we dope Y2O3 from 0% to 0.06 wt% and investigate the relationship between the different contents and the ceramic's microscopic structure and properties. A little amount of Y2O3 diffuse into the lattices and form the solid solution. What is more when x=0.048 wt%, the properties reach maximum: d33=420 p C/N, ?T33=3431, tan?=1.4%, Tc=114 ?.As a result, a proper content of Y2O3 can improve the electrical properties of the ceramic.Above all are researched at the base of Zr/Ti=5/95, aiming to improve curie temperature and keep the piezoelectric coefficient at a relatively high level. After that we focus on the optimal formula: Zr0.1Ti0.9 Ba0.85Ca0.15, and improve the electrical properties through doping and change the poling process.Doping the Sm2O3 into Zr0.1Ti0.9 Ba0.85Ca0.15, and then investigate the effects on electrical properties. The content of Sm2O3 from 0mol% to 0.4mol%, and at x=0.2 mol%, the properties are best: d33=554 p C/N, ?T33=4958, tan?=1.8%, Tc=88 ?. What I should point out is that a little amount of Sm2O3 has a great influence on microscopic structure and improve the electrical properties.At last, we research the effects of different temperatures and various field intensities on Zr0.1Ti0.9 Ba0.85Ca0.15 ceramics. The temperatures between room temperature and 600?, field intensities from 600 V/mm to 3000 V/mm, we research the poling process' s function on BCZT ceramics systematicly.