碳纳米管复合吸波涂层微波吸收性能的模拟计算

如何利用碳纳米管复合吸波涂层的参数进行吸波性能优化是电磁屏蔽研究的热点之一.涂层参数对吸波性能影响的研究主要停留在实验探索阶段,而碳纳米管的结构参数对吸波性能影响的研究鲜有报道.因此,从微观结构层次研究涂层参数对吸波性能的影响有重要意义.基于多壁碳纳米管的等效电路,利用碳纳米管结构参数与等效电路各元件参数的关系,研究了碳纳米管损耗微波的机理,建立了碳纳米管结构参数与微波反射率的关系式.根据此关系式,利用Matlab软件模拟计算了碳纳米管管长、管径、涂层中碳纳米管的含量以及涂层厚度对微波反射率的影响.模拟计算结果表明:涂层的微波反射率随碳纳米管含量变化的模拟曲线与实验结果符合;碳纳米管含量和厚度是影响吸收峰位置和吸收强度的重要参量,而碳纳米管直径和长度是主要影响吸收峰强度的参量.

Simulation and calculation of the absorbing microwave properties of carbon nanotube composite coating

How to optimize the absorbing microwave properties by using the parameters of carbon nanotube composite coating is a hotspot in the study of electromagnetic shielding. However, the study on the influence of coating parameters on absorbing microwave properties mainly stays in the stage of experimental study, and the influence of structure parameters of carbon nanotube on absorbing microwave properties has not been reported yet. Therefore, it is significant to study the method of optimizing the absorbing microwave properties of materials through micro-structure of the carbon nanotube composite coating. Based on an equivalent circuit of multi-wall carbon nanotubes, using the relationship between the parameters of each element in the equivalent circuit to study the mechanism of carbon nanotube loss microwave, an expression of absorbing microwave properties about carbon nanotube structure parameters is derived. According to the expression, the microwave reflection ratio of coating is calculated and simulated by Matlab software, which is affected by the length, diameter and coating thickness of carbon nanotube and the number of carbon nanotubes. The simulation result shows that the variation of reflection ratio curve of coating with the number of carbon nanotubes is consistent with the experimental results. The number of carbon nanotubes and the thickness of coating are the vital parameters, which influence the absorption intensity and absorption position, while the diameter and length of carbon nanotube are the vital parameters, which influence the absorption intensity.
Keywords： equivalent circuit parameters of coating absorbing properties reflection ratio