以无水乙醇为过程控制剂,利用高能球磨法将球形羰基铁粉(SCIP)制备成片状羰基铁粉(FCIP).利用扫描电镜、X射线衍射仪和振动样品磁强计考察了球磨时间对SCIP的片状化程度和电磁性能的影响.通过测定同轴样品的电磁参数确定了最佳球磨时间为15 h.以聚氨酯为基料,分别以体积分数为15%和40%的FCIP为吸收剂,制备了不同膜厚的FCIP/聚氨酯吸波涂层并互相匹配以设计出吸波性能最好的双层吸波材料,发现15% FCIP/聚氨酯1.5 mm(第一层) + 40% FCIP/聚氨酯0.7 mm(第二层)的体系在2.0 ~ 18.0 GHz下的最小反射损耗达?16 dB,反射损耗小于?10 dB的带宽为12.3 GHz.%A flaky carbonyl iron powder (FCIP) was prepared by high-energy ball milling with absolute ethanol as process control agent from spherical carbonyl iron powders (SCIP). The effect of milling time on the flaky degree and electromagnetic properties of SCIP was studied by scanning electron microscope, X-ray diffractometer, and vibrating sample magnetometer. The optimal milling time was determined to be 15 h after measuring the electromagnetic parameters of coaxial samples. Aiming to design a double-layered material with the best wave-absorbing performance, FCIP/polyurethane coatings with different thicknesses were prepared using polyurethane as the binder and FCIP with a volume fraction of 15% or 40% as the absorber, and combined with each other. The system was determined to be 15vol.% FCIP/polyurethane coating with a thickness of 1.5 mm (the first layer) plus 40vol.% FCIP/polyurethane coating with a thickness of 0.7 mm (the secondary layer). Its minimum reflectivity at the frequency range of 2.0-18.0 GHz is ?16 dB and the bandwidth of its reflection loss less than ?10 dB is 12.3 GHz.
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