Study On Preparation And Performance Of Electromagnetic Compatibility Wood-Based Panels Composite Materials

The paper mainly studies on the preparation and performance of electromagnetic comp atibility wooe-based composite material. Two aspects carriy out difference from shielding and wave-absorbing. Good conductor are used to cover the wood for shielding. It mainly discusses the choosing of adhesives and the best cementation technics about shielding, meanwhile, change of shielding effeciency after cementation is considered; It mostly studies the choosing of absorbent and the structural design of wave-absorbing within the range from 1MHz to 1.5GHzFirstly, cementation technics between wood and good conductor shielding material was studied. According to the properties of surface that will be felted, polyving acetate emulsion was selected to felt nickel plated fabric and wood-based panels, epoxy resin E-51 was selected to felt matte copper foil and wood-based panels. Then the best technics was finded from experiment. The shielding efficiency of nickel plated fabric composite panel in about 60dB and it of copper foil is reach to 70dB. The shield ing efficiency is well.Secondly, monplayer interferential loss was thinked over about wave-absorbing aspect. Selecting silicon rubber as basic material and MnZn ferrite as primary absorbent, by intermingling magnetism absorbent carbonyl iron and resistance type absorbent plumbago, it can adjust the electromagnetic parameter of compound material. This method enhanced the peak value of reflectivity and broader the valid frequency within the range from 1MHz to 1.5GHz Meanwhile, it reduced the face-density when intermingled plumbago.Then, by taking SiC as absorbent in the matching layer, taking MnZn ferrite and carbony1 iron as absorbent in the absorbing layer, it designed bilayer absorbing structure. When studyed the electromagnetic parameter and absorbing efficiency within the range from 1GHz to 1.5GHz It can optimize impedance matching and absorbing properties by changing the ratio of absorbent in matchong layer and absorbing layer. It can realize that the surface impedance of the bilayer is matching with air. So that the electromagnetic parameter of air, matching layer and absorbing layer come into gradual change, and it takes a passage for electromagnetic wave, makes the electromagnetic energy being absorbed and lossed during spreading. Then enhance the absorbing efficiency.