Analysis Of Internal Stress Effect In PZT Piezoelectric Ceramics

Based on the fundamental theories of piezoelectric ceramics, the PbZr1-xTixO3 (PZT) solid solution system is mainly discussed in this thesis. The anisotropy of elastic, dielectric and piezoelectric properties of ferroelectric ceramics is firstly introduced. Led by series of experiments phenomenon, thermodynamic theory, X-ray diffraction method and thermal expansion theory are referred to set up the internal stress model of PZT ceramics with ZrO2. After fully considered the experiment conditions of every model, improved approaches are give out separately to reduce the error level and make them more practical.The domain orientation textures of PZT ceramics due to electric poling are also mentioned in this thesis. On the basis of some saturated domain switching models, analytical unsaturated domain switching model is derived. The function expressions of domain orientation distribution after incomplete electric poling are deduced. Monte Carlo method and relevant computer programs on MATLAB platform are adopted to verify the expressions we got, and show well consistency with our conclusion.Based on the above models, take PZT ceramics with 2%～8%(mole fraction) ZrO2 for example, the theoretical curve of under hydrostatic pressure and electric poling has been derived, and basically in accordance with the experimental curve. d33...