Effect of Double-layer Coating on Microwave Absorbing Properties of Electromagnetic Shielding Fabric

Electromagnetic waves generated by electronic instruments are injected into all directions in our daily life. The absorption and consumption of electromagnetic waves is the main way to reduce the harm of electromagnetic waves. At present, the influence of double-layer absorbing materials on electromagnetic shielding fabrics has not been clarified, and few reports have been reported. In this paper, the experimental samples were tested using a high-precision reflectance test system and a shielded darkroom. In this paper, carbon nanotubes, nickel powder and ferrite were used to group stainless steel fabrics. The experiment will be divided into two groups of six groups to conduct experiments on the experimental samples: Absorbing properties of electromagnetic shielding fabrics with different types of double-layer absorbing coatings of the same kind. The same content, the absorbing properties of different types of double-layer absorbing coatings on electromagnetic shielding fabrics. The experiment found that 20% ferrite and 20% carbon nanotubes have excellent absorbing properties in this set of experiments. And the valley value appears at the frequency band of 12000 MHz and 16000 MHz. Its absolute value is about 5.8 dB and 6.3 dB; The same type, different content, the absorbing properties of the double-layer coating on the electromagnetic shielding fabric. In this set of experiments, the ferrite double layer combination has relatively low absorbing properties.20% carbon nanotubes and 30% carbon nanotube double layer coating combination. Its absorbing performance fluctuates greatly In the frequency band of 8000 MHz-18000 MHz. And the valley value appears, and its absolute value is about 4.8 dB. This experiment preliminarily revealed the absorbing properties of carbon nanotubes, ferrite and nickel powder double-layer coatings on electromagnetic shielding fabrics. It provides important data reference and academic significance for the design and production of absorbing fabrics.