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利用机械合金化方法制备了Fe1-xNix 合金纳米晶粉末 ,x分别为 0 .15、0 .45、0 .80 ,球磨时间为 2、4、8、16、40h。利用扫描电子显微镜和X射线分析仪观察和分析了样品的形貌和微结构。发现整个球磨过程可分为 3个阶段。开始阶段 ,由于冷焊 ,Fe、Ni混合粉末凝聚成一些粒径较大的颗粒 ;在中间阶段 ,内应力达到最大值 ,原先形成的大颗粒破碎 ,粒径分布变窄 ;最后阶段 ,FeNi粉完全合金化 ,粒度再次增大。至 40h时 ,可观察到层状结构。x =0 .15样品40h时形成了体心立方结构 ,而x =0 .45和 0 .80分别在 40h和 16h形成了面心立方结构。x =0 .45系列 40h以后晶粒平均粒径约为10nm ,内应力在 16h时有一极大值 0 .76 % ,在整个球磨过程中 ,测定的Ni含量偏离不超过 3 % (原子分数 )。
The Fe1-xNix alloy nanocrystalline powders were prepared by mechanical alloying method, with x values of 0.1515.0, 0.45 and 0.80 respectively and milling time of 2, 4, 8, 16 and 40 h. The morphology and microstructure of the samples were observed and analyzed by scanning electron microscopy and X-ray analyzer. Found that the entire ball milling process can be divided into three stages. In the initial stage, due to the cold welding, the Fe and Ni mixed powders are aggregated into some particles with larger diameters. In the middle stage, the internal stress reaches the maximum value, the originally formed large particles are broken and the particle size distribution is narrowed. In the final stage, Fully alloyed, particle size increases again. By 40 h, a lamellar structure was observed. The body-centered cubic structure was formed at x = 0.15 for 40 h, whereas the x = 0.45 and 0.80 formed a face-centered cubic structure at 40 h and 16 h, respectively. After 40h, the average grain size of x = 0.45 series was about 10nm, the internal stress had a maximum value of 0.76% at 16h, and the Ni content deviated by no more than 3% (atomic fraction) .