4results about How to "Improve electromagnetic absorption performance" patented technology

This invention belongs to the field of electromagnetic wave absorbing materials technology, specifically relating to an absorbing material, its preparation method, and its application. This invention uses multi-walled carbon nanotubes (MWCNTs), potassium permanganate (KMnO4), and divalent manganese as raw materials, based on Mn... 2+ With MnO4 ‑ The redox reaction between the two components allows for in-situ uniform loading of MnO2 nanoparticles onto the MWCNT surface through simple stirring in a room-temperature liquid environment, resulting in microwave absorption performance superior to most similar absorbing materials. Compared to traditional methods for preparing absorbing materials, the technical route of this invention offers significant advantages, including simple preparation process, no pollutant emissions, energy-saving and environmentally friendly process, adjustable and controllable material structure, excellent microwave absorption performance, and scalability. This method effectively overcomes the technical limitations in the preparation of absorbing materials, providing a scalable new paradigm for the green and large-scale production of high-performance absorbing materials.

This invention discloses a cobalt-based Hassler alloy material, its preparation method, and its application. The preparation method includes the following steps: (1) Weighing cobalt powder, iron powder, and germanium powder in a molar ratio of 2:(1~1.75):(0.25~1), mixing them, placing them in a tungsten carbide grinding jar, adding anhydrous ethanol, adding grinding balls, and ball milling; (2) Drying and sieving the ball-milled powder, taking the sieved magnetic alloy powder, sealing it in a vacuum quartz tube, heat-treating it using a muffle furnace, and cooling it to room temperature with the furnace to obtain a cobalt-iron-germanium Hassler alloy. This invention uses a ball milling method, which can effectively change the surface morphology of the alloy powder, making it form a flake powder with a larger specific surface area, thereby improving the electromagnetic absorption performance of the magnetic alloy; by selecting and changing the proportion of the Hassler alloy components, the saturation magnetization of the magnetic alloy can be effectively increased, its Curie temperature can be increased, and the electromagnetic wave absorption performance of the magnetic alloy at high temperatures can be improved.

This invention relates to the field of functional composite materials technology, and particularly to a high-frequency absorbing multilayer woven fabric and its preparation method. An embodiment of this invention provides a high-frequency absorbing multilayer woven fabric, which, along its thickness direction, sequentially comprises a frequency selective layer, a dielectric modulating layer, and a penetration blocking layer; the frequency selective layer comprises multiple periodically arranged periodic patterns obtained from conductor fabrication for absorbing the Ka-band. This invention provides a high-frequency absorbing multilayer woven fabric and its preparation method, which not only maintains good electromagnetic absorption in the 26-40 GHz high-frequency range, but also possesses the flexibility and durability of a fabric.

The application discloses a preparation method of carbon-based wave-absorbing coating powder for plasma spraying, a product and application thereof, and belongs to the technical field of functional materials. Lithium-aluminum-silicon gel powder, graphene oxide and N precursor are added into water and uniformly mixed, the obtained slurry is dried, and heat treatment is carried out in an inert atmosphere to obtain ceramic / graphene wave-absorbing powder; sodium silicate aqueous solution is added into the ceramic / graphene wave-absorbing powder, and stirring is uniformly carried out to obtain a wet mixed solid, and high-speed shearing is carried out to obtain a solid powder; the above operation is repeated, the finally obtained sample is dried and subjected to secondary heat treatment to obtain the carbon-based wave-absorbing coating powder for plasma spraying. Through a liquid sodium silicate foaming method, the outer layer of the ceramic / graphene wave-absorbing powder is coated with sodium silicate, the high-temperature resistance and oxidation resistance of the powder are improved, and the plasma spraying and the wave-absorbing coating are combined together, so that the application range of the coating is widened.