Tohoku University · 재료과학
벤자민 두샤르느 교수의 연구실은 전자 및 자성 물성에 기반한 비선형 히스테리시스 거동을 해석하고 모델링하는 데 중점을 두고 있습니다. 주로 페로일렉트릭 소재의 전기적 히스테리시스와 페로자성 소재의 주파수 의존성 자기 히스테리시스를 분석하며, 분수도수 미분 기반의 단순화된 수학적 모델을 활용해 복잡한 전자기기계 상호작용을 효과적으로 기술합니다. 또한 해양 파력에서의 에너지 수확 기술과 비선형 소재의 광응답 특성 연구를 통해 응용 분야로도 확장하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
The properties of ferroelectric ceramics strongly depend on the electromechanical loading and their measurement conditions. In this paper, a nonlinear phenomenological one-dimensional model based on the dry friction concept is presented to describe the hysteretic polarization behaviour. Dielectric permittivities versus dc electric field (or capacitance C versus voltage V) loops are determined for the characterization of ferroelectric material. The ε33 coefficient is used for the ceramic characte
We propose an approach to solve the coupled problem of the magnetic field penetration into soft ferromagnets and a frequency dependent magnetic hysteresis. The magnetic field diffusion is related to the macroscopic eddy currents. The hysteresis model is related to the microscopic eddy currents derived from the magnetic domain wall movements, and is responsible for the frequency dependence of hysteresis loops. In this paper, based on a lumped model and fractional derivative operators, we demonstr
We propose an original approach to solve the coupled problem of alternative magnetic field penetration inside a toroidal soft ferromagnetic sample and frequency dependent magnetic hysteresis. Local repartition of ferromagnetic losses depends on the instantaneous material properties and on the frequency of the excitation field waveform. A correct solution to the model, with respect to this repartition, implies a higher resolution in two dimensions of the diffusion equation including local dynamic
Recycling ambient energies with electric generators instead of employing batteries with limited lifespans has motivated a large scientist community over two decades. Sea waves exhibit a large energy density. The amount of energy that could be extracted from the sea waves is very high. This work describes a technique of sea wave energy extraction based on a piezoelectric conversion and an analogy with thermodynamic Ericsson loops. By synchronizing external electric field to the maximum and the mi
Post-treatment and rescaling is made possible to plot local hysteresis cycles from the measurement of local magnetic Barkhausen noise (BN). If the material is homogeneous and if similar excitation conditions are imposed, the local hysteresis cycles obtained are comparable to the classical magnetic hysteresis cycles B(H) (the cross section magnetic average induction B as a function of the surface tangential excitation field H ). These local BN hysteresis cycles provide interesting clues about the
