Investigation On Shielding Integration Compound Materials For Preventing The Information Of Broadband-frequency Electromagnetic Wave From Leakiness

In this dissertation,a new type of the shielding materials- the Shielding Integration Compound Materials(SICMs)was studied and exploited to meet the especial demand of shielding materials for preventing the information of broadband-frequency electromagnetic wave from leakiness. Firstly,on the basis of theories of material science and electromagnetic,the single-layer SICMs were designed and prepared. Secondly,the effects of vary ingredient, content ,shape and size of the fillings on shielding effectiveness(SE)in the broadband-frequency range of 14KHz～1GHz were studied. The main fillings include micron-Ni powder ,stainless steel fiber ,Fe alloy amorphous soft magnetic powder, nano-Ni powder and Fe alloy nano-crystalline soft magnetic powder. Then, two kinds of mathematical and physical models of multi-layer SICMs design were established by utilizing the integration design technology for shielding the broadband-frequency magnetic field wave and plane electromagnetic wave. And then,two types of multi-layer SICMs were studied and exploited in order to shield the broadband-frequency magnetic field wave and plane electromagnetic wave. Finally,the shielding materials were applied in commercial shielding room. The room can prevent effectively the information of broadband-frequency electromagnetic wave from leakiness. The research results may give a new design method and new kinds of materials for solving the commercial information leakiness of broadband-frequency electromagnetic wave. Therefore,this work obtains the following new creative results and progresses and reaches the expect goals.1. A new configurable model of multi-layer shielding materials was established for the first time in order to preventing the information of broadband-frequency magnetic field wave from leakiness. A new type of broadband-frequency magnetic shielding materials was designed and studied. The study results show as follows:①The design model can amplitude evidently SE of the shielding materials in the frequency range of 14KHz～1MHz. ② The SE of the shielding materials is increased with thickness of the magnetic coating. 2. A new configurable model of multi-layer shielding materials was established for the first time in order to preventing the information of broadband-frequency plane electromagnetic wave from leakiness. A new type of broadband-frequency electromagnetic shielding materials was designed and studied. The study results show as follows:①The design model can amplitude evidently SE of the shielding materials in the frequency range of. 1MHz～1GHz. ②The high-frequency SE of the shielding materials is increased with the conductivity of the intermediate electric coating. 3. The effects of ingredient, content ,shape and size of the fillings on SE of the single-layer and multi-layer SICMs were studied systematically in the range of 14KHz～1GHz. The study results in increasing SE show as follows:①Fe alloy nano-crystalline soft magnetic powder and nano-Ni powder are best, Fe alloy amorphous soft magnetic powder takes second place,stainless steel fiber takes third place,and micron-Ni powder is worst. ②slip Ni powder is better than round Ni powder. ③nano-Ni powder is better than micron-Ni powder. ④In the range of 1MHz～1GHz,the SE of the shielding materials decline differently along with frequency increasing;Fe alloy nano-crystalline soft magnetic powder descends most,and stainless steel fiber descends least. 4. The alternate effect mechanism about the new materials and the broadband-frequency electromagnetic wave,which include nano-Ni powder and Fe alloy nano-crystalline soft magnetic,Fe alloy amorphous soft powder and stainless steel fiber magnetic which are used as the fillings in the single-layer and multi-layer SICMs,was analyzed. The analyzing results show as follows:①The mechanism that Nano particle can shield effectively electromagnetic wave are as follows:1)The effective anisotropy field inside of the particle restrains magnetic domain to move,Nano particle can loss mightily the energy of...