氧化钐包覆铁纳米复合粒子的合成及微波响应特性

以Fe和Sm2O3的微米粉体为原料，压制成块体靶材，在H2＋Ar混合气氛下蒸发，原位合成了Sm2O3包覆Fe纳米复合粒子，对其成分、结构和微波频段的电磁响应特性进行了分析。结果表明，Fe／Sm2O3复合纳米粒子具有清晰的“核／壳”结构，并通过“定量氧辅助-气-液-固”机制对其形成过程进行了探讨。电磁性能分析结果显示，由介电性稀土氧化物和铁磁性‘金属构成的“核／壳”纳米结构具有微波吸收特性，其损耗机制主要以介电型损耗为主。本文采用的物理气相方法有利于多组元的纳米结构复合，实现了稀土氧化物包覆异质金属纳米胶囊合成，为金属／稀土氧化物纳米复合材料的合成与应用提供，了试验依据。

Synthesis Technology and Microwave Response Characteristics of Sm2O3-coated Iron Nanocomposite Particles

In this paper,the clumpy target was extruded with the raw materials of Fe and Sm2O3 micron powders. And then the Sm2 O3 -coated Fe nanocomposite particles were in-situ synthesized after evaporating in the mixture of H2 and Ar. After that the components,microstructures and microwave response properties of the nanocomposite particles were analyzed. The results show that the Fe/Sm2O3 nanocomposite particles have a clear core/shell type structure and then the forming process was discussed by the mechanism of ＂stoichiometric oxygen assistant VLS＇. It was also shown from the electromagnetic parameters analysis that the dielectric loss was the dominant reason in the microwave absorption properties of this kind of nanocomposite particles. The method of physical vapor applied in this paper is contribute to the synthesis of multi-component nanostructure,at the same time this method can realize the synthesis of rare earth oxides-coated heterogeneous metal nano-capsule. Meanwhile this paper provides the evidences for the synthesis and applications of the metal/rare earth oxides nanocomposite materials.