SMD as wave absorbing material
The patch is not suitable for very complicated shapes. But it can realize the complicated structure design, and the patches used are rubber, ceramic and plastic.
Structural microwave absorbing material
The non-metal composite material is used as the carrier and the absorbent is added. Usually epoxy resin and thermoplastic materials are used as the matrix, filled with ferrite, graphite, carbon black and other absorbents, such as carbon fiber/epoxy resin, graphite/thermoplastic material, boron fiber/epoxy resin, graphite fiber/epoxy resin, etc. . This type of material can not only reduce the scattering of electromagnetic waves, but also bear a certain load. It is lighter than general metal materials, has a certain strength and rigidity, and has been used.
Interference type as wave absorbing material
Interference-type microwave absorbing materials are mainly based on the interference of electromagnetic waves. At the center frequency point, the incident electromagnetic wave and the reflected electromagnetic wave have opposite phases (phase difference of 180°) and cancel each other out. This type of material is characterized by its narrow frequency range and can be used under high frequency conditions, and the material can be made thinner.
Absorbing type as wave absorbing material
The electromagnetic energy is converted into thermal energy or other forms of energy by using the large dielectric loss and magnetic loss of the incident electromagnetic wave in the object. Absorptive microwave absorbing materials are divided into electrical loss type and magnetic loss type. In general, electrical loss-type materials are better at absorbing high frequencies; and magnetic loss-type materials are more effective at absorbing low frequencies. If the two are combined, a wave-absorbing material with a wider frequency range can be made. The electrical loss type microwave absorbing material is based on carbon powder or metal particles, and a graded dielectric performance absorbing material is prepared by changing the thickness and depth and changing the type of filler. Magnetic loss type microwave absorbing material is a thin layer material filled with magnetic material such as ferrite or carbonyl iron powder, such as epoxy polysulfide, silicone rubber, urethane and fluoroelastomer.