磁电复合材料结构对磁电系数的影响

Influence of structure configuration of magnetoelectric composites on magnetoelectric coefficient

利用基于压电效应和磁致伸缩效应的本构方程,采用有限元法分别对矩形、半圆形、凸半圆形以及梯形4种不同几何形状的磁致伸缩/压电/磁致伸缩层叠复合材料的磁电响应进行研究,分析复合材料的磁电特性。结果表明:稳态时,两端为半圆形的磁电复合结构的输出电压最大,在外加直流磁场为1 000 Oe时可达76.25 V。频域分析中,两端为凸半圆形的磁电复合结构的共振频率最低,为76.5 kHz。在1 kHz时,两端为梯形结构的磁电复合结构磁电系数最大,为7.63 V/(Oe·cm),在共振时,磁电系数达到126.34 V/(Oe·cm)。进一步分析了磁电压电材料不同层叠顺序对半圆形结构复合材料磁电系数的影响,结果表明PTN层叠顺序的磁电复合结构的磁电系数最大,为5.48 V/(Oe·cm),而TPN层叠顺序型磁电复合材料的磁电系数最小,为1.64 V/(Oe·cm)。

Based on the constitutive equations of piezoelectric effect and magnetostrictive effect, the magnetoelectric responses of magnetostrictive/piezoelectric/magnetostrictive laminated composites were studied with finite element method for four different shapes including rectangular, semi-circle, convex semicircle and trapezoid. The magnetoelectric properties were analyzed for each of them.The results show that the output voltage is the largest of all for the semicircular end shape, which reaches 76.25 V with 1 000 Oe applied magnetic field.In frequency domain, the resonance frequency is 76.5 kHz for convex semicircle end shape,which is the lowest compared with other structures.It is also found that the magnetoelectric coefficient of the composite with trapezoidal end shape is the largest at frequency of 1 kHz, which is 7.63 V/(Oe·cm), and 126.34 V/(Oe·cm) at resonance.Finally, the influences on magnetoelectric coefficients of semi-circle structurecomposites were analyzedfor different stacking sequences of magnetoelectric and piezoelectric layer. The results show that the maximum magnetoelectric coefficient 5.48 V/(Oe·cm)is obtained with PTN stacked sequence, while TPN stacked sequential magnetoelectric composites produces the smallestmagnetoelectric coefficient, which is 1.64 V/(Oe·cm).