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According to scientific research, electromagnetic interference being induced by the electromagnetic radiation not only influences electrical and electronic equipment, but also endangers the human life, now it even becomes the fourth pollution in the world except the water, gas and noise. From the angle of materials, the electromagnetic shielding materials becomes more and more important in the life. At the same time, people give more requests on materials, which is light and structural component,, and electromagnetic shielding as functional material. However, the current shielding materials can not content with requests, all of them have many shortcomings, such as coating falling off easily; fibre materials distorting under unevenly stress; polymer materials lack of strength as metal. So that, preparing new functional and structural integration, which owning not only good strength but also good electromagnetic shielding effectiveness as function materials, which is very important and has a good application prospect.This paper mainly introduces the influence of the reinforcement phase on the microstructure and property in the process of preparing the cenosphere/2024Al; and the relation of density, hardness and micro-morphology of composition, in the process of plastic deformation. Testing the permeability and electromagnetic shielding effectiveness of composition and analyzing the mechanism of electromagnetic shielding. These conclusions are drawn as follows:(1)Under the temperature of 580℃,and hold 1 hour, the cenosphere/2024Al compositions are successfully prepared, and the reinforced phase are well distributed.(2)As the volume of reinforced phase increases in the composition, density and hardness also increases correspondingly, even after the plastic deformation, the improvement lever is not equal, the extruding one is higher than the forged one.(3) In the process of plastic deformation, the reinforced phase particulates are directional and orderly arranged in the pressure direction. In the process of forging, we take the multi-pass and low deformation, which reduce cracks in the bulging area of composition. The strength and plasticity of sample after extrusion are better than the one after forging, the yield strength of 30vol.%cenosphere/2024Al composition afterheat treatment is 305MPa, and the tensile strength is 405MPa.But under the same heat treatment, the yield strength after forging deformation is 298MPa, and its tensile strength is 338MPa.(4) As the volume of reinforced phase increases in the composition, the permeability of composition correspondingly increases Electromagnetic shielding effectiveness of 20vol% cenosphere/2024Al composition is 100dB.(5) The electromagnetic shielding mechanism is:the good conductivity of the 2024aluminum, and the reflection of the interface between the cenosphere and the matrix.
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