Multi-layer Structure Absorbing Composite

Main work in this paper includes four parts. Firstly, the program according as transmission line theory is compiled to calculate the absorbing property of the material. Secondly, the single layer absorbing material is made and researched. Thirdly, the analogue circuit screen absorbing material is done and studied. Fourthly, the multi-layer material which has good absorbing property at 2-4GHz.is made. Main results include:1. The material whose thickness is 4mm included 5wt% CNTs and 70 wt% CIP filled has -5dB at 4-18GHz. The material includes 70wt% CIP 5mm, 5wt% impure CNTs 1mm has -5dB at 2-4GHz, especially-10dB at 2 GHz. The material includes61 wt% (or55 wt%) CIP 1.5m, 5wt% CNTs filled with Nd 0.5mm, 50wt% ferrite 2mm,has -5dB at 2-10GHz, -8dB at 8GHz.2. The analogue circuit screen which has double screen has better absorbing property than the only one screen that is periodical. Then , CIP and ferrite is good for the materal at low frequency.3. The investigation on the analogue circuit screen is better than the material whose thickness is CIP and ferrite that is periodical.4. The main factor influences the absorbing property of the material is the effect of transmitted wave and reflected wave.