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研究了Ｗ－Ｎｉ－Ｆｅ纳米晶粉末的注射成形（ＭＩＭ）。纳米晶粉末采用机械合金化（ＭＡ）的方法制备，然后将这种纳米晶粉末与蜡基粘结剂混合以制备出喂料。讨论了ＭＡ球磨时间、纳米粉末的体积装载量和实验温度对喂料流变行为的影响。结果表明，随球磨时间增加，喂料粘度降低，粘度对剪切速率的敏感性也降低。因此，随球磨时间增加，喂料的流动性和成形性变好。随粉末装载量增加，喂料粘度呈非线性增加。喂料粘度与粉末装载量的关系为： ，其中ｎ＝０．６８。粉末经球磨后，粘度变化随温度和剪切速率的变化不大。因此，注射温度和注射速度的变化对ＭＩＭ产品的质量影响不大。
The injection molding (MIM) of W-Ni-Fe nanocrystalline powders was investigated. The nanocrystalline powder is prepared by a mechanical alloying (MA) method, and then the nanocrystalline powder is mixed with a wax-based binder to prepare a feedstock. The effects of MA milling time, volume loading of nano-powder and experimental temperature on the rheological behavior of feedstock were discussed. The results showed that with the increase of ball milling time, the viscosity of the feed decreased and the sensitivity of viscosity to the shear rate also decreased. Therefore, as the milling time increases, the fluidity and formability of the feed become better. With the increase of powder loading, feed viscosity increases nonlinearly. The relationship between feed viscosity and powder loading is: where n = 0.68. After ball milling, viscosity changes with temperature and shear rate changes little. Therefore, changes in injection temperature and injection speed have little effect on the quality of MIM products.