基于磁电效应的谐振式DC磁场传感器研究

Magnetic field sensors based on magnetoelectric (ME) effects have promising applications in electric current measurement, electromagnetic navigation and nondestructive examination owing to their superiorities in high sensitivity, cost-effectiveness, compacted size and low power consumption. Because of the dynamic coupling mechanism of magnetization-stress-electric polarization in ME composites, the ME sensors are limited in AC magnetic field sensing. The applicant’s previous researches indicate that the ME effects were manipulated by DC magnetic field. Such tunable phenomenon is especially significant when the ME composites operates in resonant state. On the basis of the discovery, the resonant state DC magnetic field sensors based on ME effects are proposed. In this project, the magnetostrictive-piezoelectric heterostructured ME composites are selected sensing units for its giant ME voltage coefficients. Multi-physics finite element method is adopted to establish fully-coupled simulation model. Due sides precision focusing cutting technique will be developed to fabricate high performance ME composite. The in-situ characterization methods will be explored to visualize magnetic domains, electric domains and stress distributions in ME composites under DC magnetic field. Multi-fields synthesized magnetic field sensor characterization platform will be used to evaluate the overall performances of the proposed sensors. By cross validations among theoretical simulation, micro-scale characterization and macro-scale calibration, the manipulating mechanism of DC magnetic field tunable effects on ME resonant states will be clarified. The implementation of this project is capable of investigating new DC magnetic field sensing mechanism, and promoting ME sensors applications in direct current transmission, electric automobile and portable electronic devices.

磁电效应传感器具有高精度、低成本、小尺寸和微功耗等优势，在电流测量、磁导航和无损检测等领域有广泛的应用前景。现有磁电效应传感器受“磁场-应力-电极化”动态耦合的制约，只对AC磁场敏感。申请人前期研究发现DC磁场对磁电效应具有调控作用，这种调控作用在磁电复合结构达到谐振状态时尤其显著。鉴于此，本项目提出基于磁电效应的谐振式DC磁场传感器研究。项目以磁致伸缩-压电复合磁电材料为研究对象，基于多物理场有限元方法建立全耦合的磁电效应仿真模型；采用双面精准对位样品切割新工艺制备敏感单元；探索DC磁场作用下的磁畴、电畴和应力分布原位表征方法；使用多因素综合测试平台标定传感器性能。最后通过理论模拟-宏观标定-微观表征三位一体的交互论证方法，揭示DC磁场对磁电器件谐振状态参量的调控机制。本项目的实施将进一步完备DC磁场传感器的检测机理，拓展磁电传感器在直流输电、电动汽车、便携式电子设备等领域的应用空间。

磁电效应传感器具有高精度、低成本、小尺寸和微功耗等优势，在电流测量、磁导航和无损检测等领域有广泛的应用前景。针对现有磁电效应传感器受“磁场-应力-电极化”动态耦合的制约，只对AC磁场敏感的原理性问题，项目组利用DC磁场对磁电效应谐振状态的调控作用，分别开发了电压、相位和频率敏感型的三种磁电效应DC磁场传感器。研究小组先后构建了磁电效应传感器的多物理场动态耦合理论分析模型，阐明了DC磁场对磁电器件谐振状态的幅值、频率及相位的调控规律，并揭示了DC磁场对磁电器件谐振状态参量的调控作用机制；在上述理论研究基础上，采用磁致伸缩材料Terfenol-D和压电材料PZT-5H复合磁电材料，利用双面精准对位样品切割工艺制备出高谐振Q值的磁电效应谐振式DC磁传感器；设计并研制了一套强磁场磁电复合材料的微观原位测量系统，并利用该系统对磁电复合材料的微小位移变化进行观察和测量，实现磁场和力场作用下磁性材料的微观原位表征。分别研制出了电压、相位和频率敏感的-磁电效应DC磁场传感模式，灵敏度分别达到32.14mV/mT、2.1 °/mT、37.509Hz/mT。其中电压输出模式的噪底和分辨率分别达到6nT/√Hz@1Hz 和 60 nT；非线性程度优于4%。本项目的开展进一步完备了DC磁场传感器的检测机理，拓展磁电传感器在直流输电、电动汽车、便携式电子设备等领域的应用空间。项目执行期间，研究小组还积极探索该DC磁场传感器在磁场成像等领域的应用研究实现了磁场探测的可视化，发表中科院一区SCI论文3篇，申请发明专利11项，授权2项，授权软件著作权5项。