用球磨机分别对Ｎｉ－５０ａｔ．－％Ａｌ和Ｎｉ－２５ａｔ．－％Ａｌ混合粉末进行机械合金化，并对Ｎｉ_３Ａｌ预合金粉末进行高能球磨，观察了粉末的金相组织，测定了粉末的硬度、平均直径和晶粒尺寸，并作了ＸＲＤ物相分析结果表明，经３ｈ研磨，Ｎｉ－５０ａｔ．－％Ａｌ混合粉末变成ＮｉＡｌ金属间化合物，其晶粒直径约５ｎｍ；经５ｈ机械球磨，Ｎｉ－２５ａｔ．－％Ａｌ混合粉末成为无序的亚稳定Ｎｉ固溶体，而Ｎｉ_３Ａｌ预合金粉末由Ｌｌ_２型长程有序金属间化合物转变为ｆｃｃ无序固溶体；球磨更长时间，则形成纳米晶． Ni-50at respectively with a ball mill. -% Al and Ni-25at. -% Al mixed powders were mechanically alloyed and Ni_3Al prealloyed powders were high energy ball milled. The microstructure of the powders was observed. The hardness, average diameter and grain size of the powders were measured. XRD analysis showed that , After 3h grinding, Ni-50at. -% Al mixed powder into NiAl intermetallic compounds, the grain diameter of about 5nm; 5h mechanical milling, Ni-25at. -% Al mixed powder becomes disordered metastable Ni solid solution, while Ni_3Al prealloyed powder changes from Ll 2 long-range ordered intermetallic compound into fcc disordered solid solution; when the ball milling is longer, nanocrystals are formed.