Flexible absorbing materials are divided into different types according to the differences in the elements and materials they contain. Absorbers of different shapes are also used in different scenarios. For example, wedge-shaped absorbing materials are often used on absorbers in microwave anechoic chambers. Coated absorbers are often used on aircraft surfaces. Absorbers have been widely used in many projects such as stealth technology, security protection, and microwave anechoic chambers. Next, we will learn more about absorbing materials from the following aspects.
Do you know what shapes flexible absorbing materials have?
- Wedge-shaped absorbing material
The absorber used in the microwave anechoic chamber is often made into a wedge shape (pyramid shape), mainly composed of polyurethane foam type, non-woven flame retardant type, silicate plate metal
- Flexible absorbing materials single-layer flat plate
The first absorber developed abroad is a single-layer flat plate, and the absorber made later is directly attached to the metal shielding layer, which is thin in thickness and light in weight, but has a narrow operating frequency range.
- Double or multi-layer flat shape
Such absorbers can operate in a wide range of operating frequencies and can be made into any shape. The disadvantage is that the thickness is large, the process is complicated, and the cost is high.
- Coated shape
Only coating-type flexible absorbing materials can be used on the surface of the aircraft. In order to broaden the frequency band, the coating of composite materials is generally used. For example, when the thickness of the lithium cadmium ferrite coating is 2.5mm to 5mm, it can attenuate 8.5dB in the centimeter band; when the thickness of the spinel ferrite coating is 2.5mm, it can attenuate 24dB at 9GHz; adding chlorine to the ferrite When the thickness of the butadiene rubber coating is 1.7mm to 2.5mm, the attenuation is about 30dB at 5GHz to 10GHz.
- Structural form
Incorporating flexible absorbent materials into engineering plastics makes them have both absorbing properties and load capacity, which is a direction for the development of flexible absorbent materials.Nowadays, in order to further improve the performance of flexible absorbent materials, complex absorbent bodies with several shapes and combinations have been developed abroad. For example, the microwave anechoic chamber made of this type of absorber in Japan, its performance is: 136MHz, 25dB; 300MHz, 30dB; 500MHz, 40dB; 1GHz ~ 40GHz, 45dB.
The wave absorbing material is mainly a shielding film with ferrite as the base material. Its main function is to absorb coupled electromagnetic waves to prevent the superposition of electric waves and eliminate redundant electric waves in the intelligent electronic system. The wave absorbing material can be cut into shape and pasted on the touch panel Anti-electromagnetic interference EMI on the back or on the cable optimizes the performance of the touch screen.
The main structure of the flexible absorbing materials:
- The principle of flexible absorbing materials is to convert electromagnetic waves emitted by electronic equipment into heat energy through insulation loss, magnetic loss, impedance loss, etc. to reduce electromagnetic radiation. It has the characteristics of high magnetic permeability and wide optional frequency band, and can be developed for specific frequency bands.
- The flexible absorbing materials has good absorption characteristics in the range of 10MHz~6GHz, which can avoid electromagnetic interference or leakage caused by secondary reflection. The main products are absorber sheet, which can also be processed into various shapes according to customer requirements. Absorbing materials can be used in cavities of electronic equipment such as notebook computers, mobile phones, and communication cabinets.
- The absorbing material has good electromagnetic wave absorption effect and wide absorption frequency. It can be customized according to the frequency band required by customers. It is thin, cost-effective, and has a wide range of uses and applications.
What are the specific applications of flexible absorbing materials at present?
With the development of modern science and technology, the impact of electromagnetic radiation on the environment is increasing. At the airport, plane flights were delayed due to electromagnetic interference. In the hospital, mobile phones often interfere with the normal work of various electronic instruments. Therefore, to control electromagnetic pollution and find a material that can resist and weaken electromagnetic radiation – absorbing material has become a major subject of material science.
The so-called flexible absorbing materials refers to a material that can absorb the energy of electromagnetic waves projected on its surface. In engineering applications, absorbing materials not only require high electromagnetic wave absorption rate in a wide frequency band, but also require light weight, temperature resistance, moisture resistance and corrosion resistance.
Electromagnetic radiation causes direct and indirect damage to the human body through thermal effects, non-thermal effects and cumulative effects. It is proved that the ferrite flexible absorbing material has the characteristics of high absorption band, high absorption rate and thin matching thickness. When this material is applied to electronic equipment, it can absorb leaked electromagnetic radiation, and can achieve the purpose of eliminating electromagnetic interference. According to the propagation law of electromagnetic waves in the medium from low permeability to high permeability, high permeability ferrite is used to guide electromagnetic waves, through resonance, a large amount of radiation energy of electromagnetic waves is absorbed, and then the energy of electromagnetic waves is converted into thermal energy.
Since its establishment, PH Functional Materials has independently developed a series of electromagnetic functional materials such as wave absorbing sheets, magnetic isolation sheets, and sintered ferrite sheets with domestic leading level. The product has the characteristics of absorbing electromagnetic waves, increasing magnetic flux, resisting metal interference and isolating magnetic fields. Flexible absorbing materials are widely used in wireless charging, RFID, NFC, EMC and other fields in electronic products. If you want to know more about our products, please contact us.
