Study On Preparation And Shielding Properties Oflightweight Carbon Cloth Composites

Light carbon cloth is widely used in many fields,such as transportation,aerospace,medical and health with its advantages of conductive,thermal conductivity,textile processing,and high compatibility.In this paper,the light-weight carbon cloth electromagnetic shielding materials were prepared by means of solution impregnated metal ion catalyst and CVD growth band of CNTs.The properties of the light-weight carbon cloth electromagnetic composites were characterized.The interrelationships among the components,structures and properties of the samples were analyzed.Firstly,metal ions were adsorbed on the surface of carbon cloth by solution impregnation method.Metal derivatives of single phase and composite phase were prepared after certain temperature treatment.It can be seen from the characterization that there are differences in the microcosmic morphology and phase composition.The ordered and disordered peak strength differences in Raman spectrum further prove that the different shielding effect on the shielding performance of carbon-based materials.Different types of single phases hydrogen reduction under high temperature conditions.Analysis shows that both Co and Ni can catalyze the growth of CNTs.Compared with Co,Ni has a higher catalytic activity.The cracking rate and diffusion rate of activated carbon in Ni catalyst particles are faster,and the content of saturated carbon atoms that can be dissolved is relatively higher.At the same time,the CNTs grown in different radial directions on the surface of the carbon cloth.The surface of the carbon rod forms a furry layer of medium.Its adjust the electromagnetic parameters,reduce the effective dielectric constant,improve the matching of electromagnetic impedance,and make electromagnetic waves enter the body of the material more.The electromagnetic waves incident on the surface of the carbon cloth occur multiple reflections and scattering inside the sample and thereby dissipating more electromagnetic energy.The content of CNTs on the surface of Co/Ni catalytically grown carbon cloth were low on the whole.Its unique hollow structure also dissipates and remains on the surface of carbon cloth were similar to carbon nanoparticle products.Based on the above,we know that the effect of carbon cloth loaded Co,Ni,Co/Ni growth CNTs and different shielding effec.First of all,its unique layered two-dimensional structure can increased the reflection loss of electromagnetic waves.Second,the large specific surface area of the composite shielding material helps to receive more electromagnetic waves.In turn,more electromagnetic waves enter thecomposite material shielding structure,lost through multiple reflections and scattering.The well conductivity of the composite shielding materials are form a micro current in the electromagnetic field to promote the attenuation of the electromagnetic wave,and improve the impedance matching of the sample.The composite shielding material are used as polarization centers to form dipole polarization,which promotes the corresponding loss of electromagnetic waves at the interface of the sample surface.The synergistic effect of two loss mechanisms enhances shielding performance of the sample.We can observe that Ni has the best overall reinforcement effect,followed by Co metal particles,and shielding effects of Co/Ni composite phase metal particles are relatively poor.