采用羰基铁为吸收剂、环氧改性有机硅树脂为基体,制备了羰基铁/树脂基涂层,研究了羰基铁用量对吸波涂层的电磁和力学性能的影响。结果表明,羰基铁经过润湿分散剂处理后,粉体与树脂间的相容性得到改善,从而提高了界面结合力,因此吸波涂层整体的力学性能得到了提高。当羰基铁含量为70%(质量分数,下同)时,复合材料的附着力为22.16MPa,冲击强度大于或等于50kg·cm。采用同轴法测试了涂层材料在2-18GHz频段内的电磁参数,并对羰基铁/环氧有机硅树脂基涂层的反射系数进行了测试,结果表明,吸波涂层的最大吸收峰随吸收荆含量的增加向低频移动。涂层厚度为2mm时,羰基铁含量为65%,涂层的最大反射率在5.12GHz时达到-32.25dB;羰基铁含量为75%,在频率为3.53GHz时材料的反射率达到最大值-36.02dB。
Carbonyl iron/epoxy-silicone coating is prepared by using carbonyl iron powder as absorber and epoxy-silicone resins as matrix. The effects of the carbonyl iron powder amount on the electromagnetic and mechanical properties of coating are investigated. The results indicate that there is good bonding state of carbonyl iron powder and epoxy-silicone resins after using the wetting and dispersing additive treatment, and the mechanical property of the absorbing coatings is increased. The adhesive power reaches to 22. 16MPa and the impact strength is larger than 50kg · cm when the amount of earbonyl iron is 70wt%. The electromagnetic and microwave absorbing properties of the coatings are studied. The results show that the minimum reflection loss shifts to the low frequency region with the increase of carbonyl iron weight concentration. When the thickness of the coatings is 2mm, the maximum reflection loss is --32. 25dB at 5.12GHz with the amount of carbonyl iron being 65wt% ; and the maximum reflection loss is --36.02dB at 3.53GHz with the amount of carbonyl iron being 75wt%.