The electromagnetic wave absorbing properties of cement-based composites using natural magnetite powders as absorber

Abstract

In order to develop a low-cost electromagnetic interference shielding and especially absorbing cement materials. In the present study, the utilization of natural magnetite in cement matrix for this purpose was investigated. The dielectric, magnetic and electromagnetic wave absorbing properties of magnetite/cement composites were characterized in the frequency range of 2.6–3.95 GHz (S band). The results show that dielectric and magnetic losses of the composites were increased, and the performance of the composites in electromagnetic absorbing is greatly improved greatly by adding natural magnetite powders as low-cost absorbers. For magnetite/composites, two matching thickness in range of 1–30 mm were clearly observed. The composites with 15% magnetite show the best absorbing property. Its strongest absorbing peak with a reflection loss of −28 dB at 3.7 GHz, and its absorbing bandwidth (<−10 dB) reaches 0.8 GHz.

Keywords

• dielectric properties
• magnetic properties
• electromagnetic wave absorbing