( 中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 在具有纳米级孔洞的多孔氧化铝模板上, 用电沉积方法制备出α-Fe纳米线有序阵列组装膜。 用10%NaOH将纳米线溶液解离， 并使之与树脂混合均匀，制成随机分布Fe纳米线/绝缘体复合吸波材料, 并对其吸波性能进行了研究。 研究结果表明： 随铁纳米线体积分数的提高， 随机分布的Fe纳米线/绝缘体复合吸波材料的电磁参数也随之增大； 用测试电磁参数计算了不同厚度的反射率， 体积分数为25%随机分布的铁纳米线/绝缘体的复合吸波材料最佳吸收厚度为1.14 mm； 在9.7 GHz时， 反射率达-45 dB， 小于-5 dB时， 反射率带宽达到9 GHz；随铁纳米线/绝缘体的复合吸波材料厚度的增加， 吸收峰位向低频移动； 随铁纳米线体积分数的增加， 其吸收率明显增大， 同时最佳吸收厚度也减小。
关键字: 多孔氧化铝模板； 纳米线阵列； 吸波性能； 反射率
iron nanowire composites distributed randomly
（ State Key Laboratory for Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract: The α-iron nanowires array films were prepared by electrochemical deposition on the porous anodic aluminum oxide template with nanopores. The α-iron nanowires were liberated in the 10% NaOH solution and equably mixed with resin. Then, the iron nanowire/ nonconductor composites distributed randomly were prepared， and the microwave absorbing properties of composites were studied. The results show that the electromagnetic parameters of the absorbing materials increase with increase of the iron nanowires volume fraction. Reflection coefficients of the absorbing materials were calculated with the electromagnetic parameters tested. The optimal absorbing thickness of iron nanowires composites with 25% volume fraction is 1.14 mm. When the frequency is 9.7 GHz, the reflection coefficient is -45 dB, and when the reflection coefficient is less than -5 dB, the broad band is 9 GHz. The location of reflection coefficient apex is moved to the low frequency with the thickness of absorbing material increasing. With increase of the iron nanowires volume fraction, the reflection coefficients increase greatly and the optimal thickness decreases at the same time.
Key words: porous anodic aluminum oxide template；nanowire array；microwave absorbing properties；reflection coefficient
