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利用透射电镜和Ｘ射线衍射技术研究了Ｍｏ－３６．５％Ｓｉ、Ｍｏ－４５％Ｓｉ和Ｍｏ－６６．７％Ｓｉ混合粉在机械合金化过程中的相结构变化。经长时间球磨后，这三种粉都可以转变为非晶；不同成分混合粉的中间产物并不相同，中间产物的差异导致了不同成分的Ｍｏ－Ｓｉ系非晶转变的机制不同。Ｍｏ－３６．５％Ｓｉ的非晶化过程是首先形成亚稳相的过饱和固溶体，然后形成了非晶，此时，Ｍｏ和Ｓｉ原子的尺寸因素是非晶转变的决定因素。Ｍｏ－４５％Ｓｉ和Ｍｏ－６６．７％Ｓｉ混和粉则是首先形成了金属间化合物，然后形成了非晶相，此时，缺陷为非晶转变的决定因素。
The phase structure of Mo-36.5% Si, Mo-45% Si and Mo-66.7% Si powders during mechanical alloying was investigated by transmission electron microscopy and X-ray diffraction. After milling for a long time, the three kinds of powders can be transformed into amorphous. The intermediate products of mixed powders of different compositions are not the same. The difference of intermediate products leads to different mechanism of amorphous transformation of Mo-Si amorphous components. The amorphization process of Mo-36.5% Si is the first to form a supersaturated solid solution of a metastable phase and then to an amorphous phase. In this case, the size factors of the Mo and Si atoms are the determinants of the amorphous transition. Mo-45% Si and Mo-66.7% Si mixed powder is the first to form an intermetallic compound, and then formed an amorphous phase, the defect at this time is the deciding factor for the amorphous transition.