核壳型磁性颗粒微波磁导率模拟与实验研究

Simulation and experimental study of microwave permeability of magnetic particles with core-shell type

采用有效媒质理论模拟和实验验证的方法，研究了核壳型磁性颗粒的微波磁导率。结果表明：核壳结构有利于提高微波下颗粒的复磁导率，2GHz时，其实部比氧化后的颗粒提高6％-12％，虚部提高15％～30％。片状椭球形核壳结构优于球形核壳结构，2GHz时，20nm壳层厚的片状颗粒的复磁导率为4．85—1．71 i，而同壳层厚的球状颗粒为4．55—1．31 i。在核壳结构的颗粒中，壳层厚度薄有利于改善磁导率。

Microwave permeability of magnetic particles with core-shell type were investigated by methods of simulation of effective medium theory and experimental verification. Results show that microwave complex permeability is advanced via core-shell microstructure of particles, the real-part with core-shell is increased 6%-10% than oxidized particles in 2 GHz, and the imaginary-part is increased 15%-30% too; The flake-like particles with core-shell is superior to sphere ones, complex permeability of flake-like particles of 20 nm thickness is 4.85-1.71 i, but ones of sphere-like particles of 20 nm thickness is 4.55-1.31 i in 2 GHz; with decreasing the thickness of particle shell, complex permeability of magnetic materials is improved.