Lou Guofeng, Yu Xinjie, Lu Shihua
State Key Lab of Power System, Department of Electrical Engineering, Tsinghua University, Beijing 100084, China.
Sensors (Basel). 2017 Jun 15;17(6):1399. doi: 10.3390/s17061399.
This paper describes the modeling of magnetoelectric (ME) effects for disk-type Terfenol-D (TbDyFe)/PZT (Pb(Zr,Ti)O₃) laminate composite at low frequency by combining the advantages of the static elastic model and the equivalent circuit model, aiming at providing a guidance for the design and fabrication of the sensors based on magnetoelectric laminate composite. Considering that the strains of the magnetostrictive and piezoelectric layers are not equal in actual operating due to the epoxy resin adhesive bonding condition, the magnetostrictive and piezoelectric layers were first modeled through the equation of motion separately, and then coupled together with a new interface coupling factor , which physically reflects the strain transfer between the phases. Furthermore, a theoretical expression containing for the transverse ME voltage coefficient and the optimum thickness ratio to which the maximum ME voltage coefficient corresponds were derived from the modified equivalent circuit of ME laminate, where the interface coupling factor acted as an ideal transformer. To explore the influence of mechanical load on the interface coupling factor , two sets of weights, i.e., 100 g and 500 g, were placed on the top of the ME laminates with the same thickness ratio in the sample fabrication. A total of 22 T-T mode disk-type ME laminate samples with different configurations were fabricated. The interface coupling factors determined from the measured and the DC bias magnetic field were 0.11 for 500 g pre-mechanical load and 0.08 for 100 g pre-mechanical load. Furthermore, the measured optimum thickness ratios were 0.61 for = 0.11 and 0.56 for = 0.08. Both the theoretical ME voltage coefficient and optimum thickness ratio containing agreed well with the measured data, verifying the reasonability and correctness for the introduction of in the modified equivalent circuit model.
本文结合静态弹性模型和等效电路模型的优点，描述了盘式Terfenol-D（TbDyFe）/PZT（Pb（Zr，Ti）O₃）层压复合材料在低频下的磁电（ME）效应建模，旨在为基于磁电层压复合材料的传感器的设计和制造提供指导。考虑到由于环氧树脂粘结条件，磁致伸缩层和压电层在实际工作中的应变不相等，首先通过运动方程分别对磁致伸缩层和压电层进行建模，然后用一个新的界面耦合因子将它们耦合在一起，该因子从物理上反映了相之间的应变传递。此外，从磁电层压板的改进等效电路中推导出了包含横向磁电电压系数和最大磁电电压系数对应的最佳厚度比的理论表达式，其中界面耦合因子充当理想变压器。为了探究机械负载对界面耦合因子的影响，在样品制备过程中，将两组重量分别为100 g和500 g的重物放置在具有相同厚度比的磁电层压板顶部。共制备了22个不同配置的T-T模式盘式磁电层压板样品。对于500 g的预机械负载，由测量的和直流偏置磁场确定的界面耦合因子为0.11，对于100 g的预机械负载为0.08。此外，测量得到的最佳厚度比对于=0.11为0.61，对于=0.08为0.56。包含的理论磁电电压系数和最佳厚度比与测量数据吻合良好，验证了在改进等效电路模型中引入的合理性和正确性。
