Flexible absorbing material refer to a class of materials that can absorb the energy of electromagnetic waves projected on its surface. In engineering applications, in addition to requiring the absorbing material to have a high absorption rate of electromagnetic waves in a wide frequency band, it is also required to have light weight, temperature resistance, moisture resistance, corrosion resistance and other properties.
Introduction to flexible absorbing material
Flexible absorbing materials are the product of the expansion of absorbing materials, which emerged with the rise of electric power, electrical and telecommunication technologies, and have a wide range of applications. Flexible absorbing materials are mostly used in the electrical field and information field , the automotive field and other supporting fields, the most important thing is that flexible absorbing materials are the main raw materials for the production of electronic components, which bring far less demand. In electronic equipment, the high-frequency noise generated by the flat circuit will cause instability to the system. The limited area of the circuit board is wide, and it is impossible to install a filter in the flat shape. At this time, flexible absorbing materials are used to cover the entire circuit. Interfering surfaces form absorption heat transformations.
The application types of flexible absorbing materials are mainly divided into sheets and echo-free anechoic chambers. Since materials with different thicknesses have different attenuation effects on cavity resonance in different frequency bands, flexible absorbing materials with different thicknesses can be selected for different applications. In general, the effective thickness of a flexible absorber is proportional to the wavelength of the target application, or inversely proportional to the frequency. One of the main applications of anechoic chamber is EMC testing, among which the most commonly used is anechoic chamber testing in the fields of automobiles, microwave antennas, radar, aerospace and other fields, while all electronic products (such as electronic components, medical imaging equipment, communications equipment, digital cameras, mobile phones) also need to be tested in the dark room. At the same time, the parameters of the darkroom test will be different according to the test target.
Features of flexible absorbing materials
- Suitable for EMC absorbing materials, the maximum initial permeability is as high as 135, and the permeability characteristics are excellent;
- Excellent electromagnetic absorbing effect in broadband (10MHZ-3GHZ);
- Applicable to various cables such as mobile phones, FPC, computers, IC chips, LCD/digital camera motherboards, PDP/digital cameras, etc.
Classification of flexible absorbing materials
Flexible absorbing materials can be divided into two types: traditional and new flexible absorbing materials.
Among them, traditional flexible absorbing materials are divided into resistive absorbing materials, dielectric absorbing materials and magnetic medium absorbing materials according to their microwave loss mechanism.
New flexible absorbing materials include: nanomaterials, polycrystalline iron fibers, chiral materials, conductive polymer absorbing materials, plasmonic absorbing materials and visible light, infrared and radar compatible absorbing materials, etc.
The future development trend of flexible absorbing materials:
As the operating frequency of the circuit continues to increase, the cavity of the circuit board continues to decrease, and cavity resonance has become an increasingly common problem. There are many ways to solve this problem, superb engineering design can solve this problem. But the quickest and most economical method is to use flexible absorbers to attenuate cavity resonances. Many microwave circuit designers nowadays have encountered this situation.
Condition: After placing the board inside the board housing, the board does not function as expected. The reason is that after the circuit board is put into the cavity, the microwave signal will resonate in the cavity, and the cavity resonance will cause the circuit impedance condition to change, and the specific impedance condition is very important for the normal operation of the microwave circuit.
Cavity resonance can be a problem because the designed circuit must be shielded with a board cover, and it is when adding a board cover that problems can arise. For the purpose of electromagnetic shielding, the circuit board cover is usually made of metal material. This creates a cavity above the circuit board, which induces resonance. The use of microwave absorbing materials in the cavity to attenuate cavity resonances is an extremely effective method. Flexible absorbing materials use the principle of electromagnetic energy conversion to convert electromagnetic energy into heat energy without reflection and secondary pollution.
In daily life, such as smartphones, POS machines, RFID radio frequency cards, card readers, various access control cards, antennas, etc., almost everyone in the streets and alleys. In the future, people’s needs for these will become more and more ambitious, and their use will become more and more frequent. In addition, China’s radio waves imply a surge in demand, and the development of flexible absorbing materials is very optimistic.
Shenzhen PH Functional Materials specializes in the production of electromagnetic absorber and shielding materials, and the company can customize it according to the relevant needs of customers. The same product, better quality, more suitable price, more thoughtful service. PH will also make various efforts to produce world-class quality products in flexible electromagnetic wave suppression, magnetic isolation sheets, ultra-high frequency magnetic sheets, etc. At the same time, it will further reduce costs through technological updates and management progress, and is committed to providing the market with More high-quality and cheap products, make due contributions to the development of the industry.
