Wersing W, Lubitz K, Mohaupt J
Siemens AG, Munich.
IEEE Trans Ultrason Ferroelectr Freq Control. 1989;36(4):424-33. doi: 10.1109/58.31779.
Experimental and theoretical investigations of the electromechanical anisotropy of ceramics modified with Ca, Ni-Nb, and Mn are presented. It is demonstrated that the large anisotropy of these ceramics is neither a bulk property of the PbTiO(3)-crystallites nor a domain wall effect. The anisotropy is caused by the statistical orientation of the crystallites in the ceramics and by the material properties due to this orientation. The ratio of electrostrictive coefficients and the ratio of single-crystal permittivities in these ceramics also play a decisive role. The result enables one to comprehend easily the dependence of the ceramic's electromechanical anisotropy on the material composition, the degree of poling, and the temperature.
本文介绍了对用钙、镍-铌和锰改性的陶瓷的机电各向异性进行的实验和理论研究。结果表明，这些陶瓷的大各向异性既不是钛酸铅（PbTiO₃）微晶的体性质，也不是畴壁效应。各向异性是由陶瓷中微晶的统计取向以及由于这种取向而产生的材料特性引起的。这些陶瓷中电致伸缩系数的比值和单晶介电常数的比值也起着决定性作用。该结果使人们能够轻松理解陶瓷机电各向异性对材料成分、极化程度和温度的依赖性。
