高产率纳米铁粉的制备及表征

采用循环水冷却和循环等离子体工作气体的改进方法，制备出纳米铁粉。当电流为500A，气体总压为0．03MPa，电压为32V，氢气含量为50％，风机转速为2400r／min时，铁粉产率可高达6．2g／min，其平均粒径为50nm。粒子大多呈球形，表面光滑，粒子大小均匀，连接成链状。但是有些大颗粒粒径达到微米级，这主要是团聚所致。实验中制备的纳米铁颗粒为层状结构，由内到外依次是Fe-Fe3O4—Fe2O3，Fe3O4和Fe2O3的含量很低，但起到了对纳米粒子的保护作用。

Preparation and Characterization of High Productivity Nanometer Iron Powder

Nanometer iron powder was prepared by utilizing modified the circulating water and plasma gas. When the current, total pressure, voltage, H2 content and fan rotating rate are 500 A, 0.03 MPa, 32 V, 50% and 2 400 r/min respectively, the yielding output can reach up to 6.2 g/min and the average diameter of powder is 50 nm. Most of nano-iron powder are spherical and has smooth surface, the size of particles is uniform and these particle is chainlinked. However, some particles have micro-magnitude size due to the congregation. Nano-iron powder has core-shell structure, the outer shell and the core correspond to oxide and Fe. The order is Fe-Fe3O4-Fe2O3 from the inner to the outer. The content of Fe3O4 and Fe2O3 is very low, but they play a protective role for nanometer particles.