Absorption principle and absorption performance testing of flame-retardant absorbing materials

Flame retardant absorbing materialIt is an electrical loss absorbing material that adopts a geometric cone structure to achieve good matching of radio waves. When the radio waves are vertically incident, the impedance of the absorbing material gradually changes from 377 Ω to 2 Ω, avoiding reflection on the front surface of the absorbing material; Due to the good conductivity of the absorbing material, radio waves entering the interior of the absorbing material can quickly convert electromagnetic energy into Ohmic energy and absorb and attenuate the radio waves.

Assuming the reflection loss of the absorbing material is R, when the thickness of the absorbing material is equal to the wavelength ratio t/λ=0.2, R can reach -14dB; When t/λ=1, R is -31dB; When t/λ=7, R is -50dB. The absorption performance test adopts low-frequency coaxial reflection method in 30-600MHz, waveguide method in 600-1000MHz, and RCS comparison method in 1-40Hz. The analysis and actual measurement results indicate that flame-retardant absorbing materials have good low-frequency performance and large angle performance.

Safety performance of flame-retardant absorbing materials:

Excellent fire resistance: This material isInorganic carrierAccording to GB/T2406-93 "Test Method for Combustion Performance of Plastics - Oxygen Index Method", the material has an oxygen index of over 60%, which meets the requirements of GB8624-1997 "Classification Method for Combustion Performance of Building Materials" and is classified as B1 level flame-retardant material.

Capable of withstanding high power: For microwave power irradiation below 15 kilowatts per square meter, no ventilation or cooling facilities are required. The performance indicators of flame ignition and propagation, conductivity, and internal heat testing show that they exceed the requirements of NRL Report NO8093 (tests 1, 2, and 3) for three experiments conducted by the US Navy.

Environmental performance of flame-retardant absorbing materials:

According to GB/T14677-93 "Methods for Monitoring and Analyzing Air and Waste Gas", the air in the darkroom was tested, and the human health environment in the darkroom met the Chinese living environment standards. Absorbing materials themselves have no pollution to the environment, and there is no concern of secondary pollution treatment due to scrappingEnvironmentally friendly absorbing materialsThe material has stable chemical properties, no odor, no harmful gas emissions, no powder shedding or color fading, no moisture absorption, and a cleanliness level of up to 100000.

Structure and performance of flame-retardant absorbing materials:

The absorbing material is top-notch and does not bend or sag for long-term use, with a lifespan of over 15 years. The absorbing cone is arranged neatly vertically and horizontally, with a firm and flat appearance, and the cone is not bent or flat headed; The bottom side is level and free of debris; The appearance is clean, the color is uniform and consistent, and the hand feel is smooth without fading. Within the shelf life, there is no cracking, discoloration, or deformation.

In addition to conventional conical materials of different heights, flame-retardant absorbing materials also include broadband hard absorbing flooring, diverging corners, converging corners, ventilation, lighting and other special materials. Flame retardant absorbing materials are installed by hanging metal components.

There are three installation methods for absorbing materials: pasting, hanging, and adsorption. Flame retardant absorbing materials are hung on metal surfaces and can be put into use immediately after installation without the need for adhesive evaporation waiting period. If the material needs to be replaced, it is very convenient.