复合助剂高能球磨对羰基铁粉低频吸波性能的影响

Effect of low frequency wave-absorbing performance of carbonyl iron powder with compound auxiliary agent by high-energy ball milling

采用单一助剂硅烷偶联剂KH-560、表面活性剂硬脂酸钙和复合助剂（KH-560＋硬脂酸钙）分别通过高能球磨制备片状羰基铁粉吸波材料的样品,系统地分析研究样品的微观形貌、物相、电磁参数,并通过电磁场传输线理论模拟计算吸波涂层反射损耗。结果表明：与单一助剂样品相比,复合助剂样品团聚现象明显减少,形成了平整、光滑的片状结构;模拟计算在2 mm厚度下,反射损耗小于–10 d B,复合助剂样品带宽达到1 GHz（1.4～2.4 GHz）,且在2 GHz处的反射损耗峰值也达到–15 d B,均优于单一助剂样品。复合助剂的使用可以增强偶联剂和表面活性剂在片状羰基铁粉颗粒的表面包覆效果,达到更好的介电调控目的,提高低频吸波性能。

Absorbing material samples of flaky carbonyl iron powder were respectively prepared by using three auxiliary agents （silane coupling agent KH-560, surfactant calcium stearate and compound auxiliary agent of KH-560 ＋ calcium stearate） and high-energy ball milling. The morphology, phase and electromagnetic parameters of the samples were sys-（ematically investigated. Reflection loss was also calculated through the electromagnetic transmission line theory. It is found that compared with other samples by single auxiliary agents, the sample produces less aggregation by compound auxiliary agent and possesses flat and smooth flaky texture. Results also suggest that for the sample by compound auxiliary agent, the frequency range of reflectivity with a coating thickness of 2 mm under -10 dB reaches 1 GHz （1.4-2.4 GHz）, and the minimum reflectivity is -15 dB at 2 GHz, which were far better than those of samples by single auxiliary agents. Effect of surface coating is enhanced by compound auxiliary agent on flaky carbonyl iron powder. Electromagnetic parameters can also be adjusted, that is helpful to improve the low frequency wave absorbing performance.