基于多模式耦合振动的压磁压电复合材料结构的优化设计

Structural Optimization of Piezoelectric and Piezomagnetic Composite Materials based on the Coupled Vibration Modes

多铁性材料磁电复合结构的单一振动模式可分为纵向振动、径向振动和弯曲振动。本文提出的多模式耦合振动的概念,是指多个独立的振动模式通过一定的耦合方式共同对系统的磁电效应作出贡献。本文分析了径-纵耦合振动模式的Core-Shell模型。结果表明,调节与各振动模式对应的尺寸,可以改变不同振动模式的振动状态,当不同振动模式的共振峰靠近或重合时,可以实现比单一振动模式更为理想的磁电效应。另外,从结果中可以看到,Core-Shell模型中当不同振动模式所对应的共振峰重合时,磁电系数有了非常显著的提高。本文提出的多模式耦合振动的概念,可为多铁性材料磁电复合结构优化设计提供理论指导。

The longitudinal,radial and bending modes are the three typical vibration modes realized in the magnetoelectric devices made of multiferroic composites.The coupled vibration modes were proposed,in order to enhance the magnetoelectric coupling coefficients,which is much larger than the simple addition of coefficients contributed by the individual vibration mode.A Core-Shell structure was analyzed theoretically to demonstrate this new concept.This structure is of coupled longitudinal and radial modes.The analysis shows that the resonance peak is pertinent to the structure dimension.By optimizing the geometric parameters,the resonance peaks from separate modes can be shifted.When two peaks coincides with each other,the magnetoelectric coefficient can be increased in orders.A theoretical framework is thus underlain and developed,which is highly useful in guiding the device design and structure optimization.