격자형 자성 복합재의 전파흡수 특성

• Published in: 대한금속·재료학회지, 50(5) Vol. 50; no. 5; pp. 389 - 393
• Main Authors: 박명준, Myung Joon Park, 김성수, Sung Soo Kim
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 20.05.2012; 대한금속·재료학회
• Subjects: composites; computer simulation; magnetic properties; microwave absorbers; powder processing; 재료공학
• ISSN: 1738-8228; 2288-8241
• DOI: 10.3365/KJMM.2012.50.5.389

Improvement in microwave absorbance has been investigated by insertion of a periodic air cavity in rubber composites filled with magnetic powders. A mixture of Co2Z hexagonal ferrite and Fe powders were used as the absorbent fillers in silicone rubber matrix. The complex permeability and complex permittivity of the magnetic composites were measured by reflection/transmission technique. In the grid-type magnetic absorbers, the equivalent permeability (εeq) and permittivity (εeq) are calculated as a function of air volume rate (K) on the basis of effective medium theory. Reduction in the material parameters (especially, dielectric permittivity and magnetic loss) has been estimated with the increase of K. Plotting the εeq and εeq on the solution map of wave-impedance matching, wide bandwidth microwave absorbance has been predicted in the magnetic composites with an optimum value of K.