X-band 대역 스피넬 페라이트-Epoxy 전자기파 흡수 특성

Abstract

Purpose: With the recent development of the wireless electronics industry, the problem of electronic self-interference has emerged. To solve this problem, research on electromagnetic (EM) absorbers have increased. To contribute to the imaginary part of complex magnetic permeability, absorbing electromagnetic waves and releasing them as heat has increased, and through this, we studied the composition of electromagnetic wave absorbers using spinel ferrite.<BR>Methods: Single cubic spinel ferrites, (Ni<SUB>0.5</SUB>Zn<SUB>0.5</SUB>)1<SUB>-x-y</SUB>Co<SUB>x</SUB>Cu<SUB>y</SUB>Fe₂O₄ (x = 0.0 and y = 0.0, x = 0.4 and y = 0.0, x = 0.2 and y = 0.2, x = 0.0 and y = 0.4) were prepared using solid-state reactions and post-annealing processes. The sample powders were annealed at 1100°C for 4 h in air. Subsequently, the samples were ground to fine powders. The spinel ferrite powder and epoxy binder were mixed at a 10 wt% ratio and pressed into toroidal-shaped (inner: 3.04 mm, outer: 7.00 mm) green compacts at a pressure of 0.3ton, and finally cured at 180℃ for 20min in air.<BR>Results: (Ni<SUB>0.5</SUB>Zn<SUB>0.5</SUB>)1<SUB>-x-y</SUB>Co<SUB>x</SUB>Cu<SUB>y</SUB>Fe₂O₄ (x = 0.2 and y= 0.2) samples, RL < -16.4 dB (EM energy absorption above 90%) is satisfied in the X-band EM wave absorption frequency range (8-12 GHz) with d = 2.95 mm.<BR>Conclusion: The Co and Cu substituted Ni-Zn ferrite-epoxy composite is applicable for the development of 8-12 GHz-range EM wave absorber.