海胆状氧化锌/羰基铁粉核壳结构复合粒子的抗氧化及吸波性能

针对羰基铁粉吸收剂在温度较高时易被氧化的问题,采用水热法制备了氧化锌包覆羰基铁粉核壳结构复合粒子,并分别将羰基铁粉和氧化锌/羰基铁粉核壳粒子与石蜡混合,制备复合材料。结果表明,氧化锌纳米棒致密的包覆在羰基铁粉颗粒表面形成海胆状核壳结构复合粒子,正是这种结构将羰基铁粉颗粒与空气隔绝,使得复合粒子的抗氧化性能得到显著改善。与羰基铁粉复合吸波材料相比,氧化锌/羰基铁粉核壳粒子的复合材料吸收峰稍向低频移动,反射损耗小于-5 d B的带宽几乎保持不变,在不改变电磁吸波性能的前提下,提高了羰基铁粉粒子的使用温度。

Oxidation Resistance and Microwave Absorption Property of Core Shell Urchin-like ZnO\Carbonyl Iron Powder Composite Particles

In order to solve the weak oxidation resistance of carbonyl iron powder at higher temperature, carbonyl iron powders with core-shell coated ZnO were prepared using hydrothermal method and then the composites were fabricated by mixing the absorbent in the paraffin matrix. The results show that the carbonyl iron powders are coated by ZnO nano-roads, forming core-shell urchin-like composite particles. Due to this structure, the carbonyl iron powders are isolated from oxygen and thus the oxidation resistance can be improved. Compared with the absorbing materials consisting of pure carbonyl iron powders, the absorption peak for ZnO/carbonyl iron powder shifts towards the low frequency slightly, but the bandwidth of reflection loss below -5 dB is almost unchanged. The results suggest an alternative approach to improve the oxidation resistance of the carbonyl iron powders without influencing their microwave absorption properties.