【作者】 方志刚； 李处森； 张劲松；

【Author】 FANG Zhi-gang1,LI Chu-sen2,ZHANG Jin-song2(1 College of Mechanical Engineering,Taizhou University,Taizhou 318000,China;2 Institute of Metal Research,The Chinese Academy of Sciences,Shenyang 110016,China)

【机构】 台州学院机械工程学院； 中国科学院金属研究所；

【摘要】 通过改进的有机泡沫浸渍法制备了具有宏观三维连通网络结构的炭泡沫。研究表明,热解温度对炭泡沫的电导率有重要影响,随着热解温度的提高,炭泡沫的电导率快速增加。炭泡沫的电导率对其吸波性能有直接的影响,电导率过大或过小时,炭泡沫的吸波性能均不佳,电导率为0.46 S/m的炭泡沫具有最佳的宽频带吸收特征,在4～15 GHz频段上的平板反射率达到-6～-8 dB。按照吸波材料的多层设计理念和"阻抗渐变"的设计思路,将炭泡沫组合成电导率、体积分数均渐变的多层结构,得到的炭泡沫组合体具有优异的吸波性能,在2.6～18 GHz全频段上反射率均超过-10 dB,最低反射率-32 dB。更多还原

【Abstract】 Carbon foams,which characterize three-dimensional reticulated structure,were prepared by a modified polymer sponge replication process.Experimental results show that the electric conductivity of carbon foams increases gradually with the improvement of carbonization temperature.The electric conductivity of carbon foams has a direct effect on the microwave absorbing property when other parameters are fixed at constants.Carbon foams with too low or too high electric conductivities can not get excellent microwave absorbing properties,but the carbon foam with a electric conductivity of 0.46 S/m have got a more excellent microwave absorbing property and demonstrated the characteristic of broadband absorption,as the reflectivity reaches-6～-8 dB on the frequency range of 4～15 GHz.According to the conception of multilayer structure and gentle impedance transition for microwave absorb materials,a carbon foam combination multilayer structure was designed.In this carbon foam combination multilayer structure,the electric conductivity and volume fraction of carbon foams were designated to change gradually from the top layer to the bottom layer.An excellent broadband microwave absorbing property,specifically,the reflectivity reaching-10 dB at the whole frequency range of 2.6-18 GHz and the minimum reflectivity reaching-32 dB,has got for the carbon foam combination multilayer structure,which has been seldom reported elsewhere.更多还原