纳米晶W粉和W-Ni-Fe预合金粉的制备

采用高能球磨法制备纳米晶W粉和W-Ni-Fe预合金粉，研究了不同的球磨材质包括硬质合金球(CCB)、钨球(TAB)和球磨转速、球料比及球磨时间等条件对球磨后粉末性能的影响。利用XRD，TEM和EDX分析球磨后粉末的晶粒尺寸、晶格畸变、形貌、结构变化及颗粒成分变化。结果表明：高能球磨法可制得10nm～80nm的W粉和W-Ni-Fe预合金粉，纳米级颗粒含量达80％以上。相同材质的钨球制得的纳米粉末综合性能较好。球磨过程中，粉末保持颗粒状结构，纳米级粉末颗粒形状最终趋于等轴化。

Preparation of Nanocrystalline Tungsten Powder and Tungsten-Nickel-Iron Prealloyed Powder

Nanocrystalline W powder and tungsten based W-Ni-Fe prealloyed powders were prepared by high-energy ball milling. The influences of: (i) milling media including cemented carbide balls (CCB) and tungsten alloy balls (TAB), (ii) rotational speed, (iii) ratio of ball to powder, and (iv) grinding time on powder characteristics were studied. The grain size, lattice deformation and morphology, of the component of particles after milled were analyzed by means of XRD, EDX and TEM. The results showed that nanocrystalline powders with size of 10nm to 80nm could be synthesized by high-energy ball milling. The percentage of nanocrystalline particles in the powders is up to 80%. The overall properties of the nanocrystalline powders prepared using the TAB milling medium was better than those prepared by CCB milling. During milling the morphology of the nanocrystalline powder evolves from spherical to granular.