压电材料机电耦合参数测试试件的优化设计OA

In the measurement of the transverse piezoelectric coefficient e31 of piezoelectric materials,the test precision of the test specimen has a significant effect on the test results.Therefore,it is necessary to establish an accurate model to predict the performance of the piezoelectric specimen accurately.In the e31 measuring method,the PZT specimen can be seen as a bilayer piezoelectric beam which consist of piezoelectric layer and elastic layer.To analyze the influence of the laminated piezoelectric beam structure on the measuring results of e31,a bilayer piezoelectric beam model is established based on the classical piezoelectric theory.The governing equations and boundary conditions are derived by using the minimum potential energy principle.The general solution of the governing equations is obtained.The validity and reliability of the present bilayer piezoelectric beam model are validated by the existing experimental data.The influence of different structural parameters of the piezoelectric specimen on the test results is analyzed.It is found that the measurement accuracy of the lateral piezoelectric parameter e31 is directly proportional to the deflection of the beam.Among the key parameters of length,width,and thickness of the piezoelectric specimen,under voltage load,the width of the specimen has the smallest influence on the deflection,so the effect of width on the measurement accuracy of e31 can be neglected.The length of the specimen is directly proportional to the deflection,so to improve the measurement accuracy,the length of the piezoelectric beam should be increased.The thickness has a significant influence on the piezoelectric parameter e31.When the elastic layer thickness is 100 times greater than the piezoelectric layer,the influence of the piezoelectric layer on the beam bending can be neglected in the e31 measurement.