采用商用FeNi30及FeNi50合金粉为原料通过机械合金化(MA)合成纳米晶Invar合金(FeNi36)粉体,研究了不同球磨时间的Invar合金粉体的物相组成、显微组织结构与形貌特征,探讨其合金化机制。结果表明:球磨初期(5~10 h),微锻造和冷焊过程使合金粉体呈扁平形复合层状结构,同时FeNi50中的Ni原子逐渐向FeNi30中扩散,发生成分均匀化;球磨40 h后,已形成了成分均匀的α’-Fe(Ni)固溶体,其平均晶粒尺寸约为12 nm。此时,机械合金化合成的Invar合金粉体呈球形,表面光滑,继续球磨,大颗粒粉体表面出现裂纹,并碎裂,导致粉体细化。 The commercial FeNi30 and FeNi50 alloy powders were used as raw materials to synthesize nanocrystalline Invar alloy (FeNi36) powders by mechanical alloying (MA). The phase composition, microstructure and morphology of Invar alloy powders were studied at different milling times , To explore its alloying mechanism. The results show that during the initial ball milling (5 ~ 10 h), the micro-forging and cold welding process make the alloy powder flat and complex layered structure. At the same time, the Ni atoms in FeNi50 gradually diffuse into the FeNi30, After the formation of a uniform composition of α’-Fe (Ni) solid solution, the average grain size of about 12 nm. At this moment, the alloy of Invar alloy synthesized by mechanical alloying has a spherical shape with a smooth surface and continues to be ball-milled. Cracks on the surface of the large particle powder and chipping occur, resulting in the refinement of the powder.