钼硅混合粉末在机械合金化过程中的结构演变

采用X射线衍射仪（XRD）和差热分析仪（DTA）研究了Mo-67at%Si元素混合粉末在中等强度的机械研磨（合金化）过程中的结构变化过程，结果表明，在中等强度的研磨过程中，β－MoSi2是初生相，且在随后的研磨过程中非晶化；在高研磨强度下生成α－MoSi2的量大于β－MoSi2,且α－MoSi2的含量随研磨时间的增加而增加，差热分析表明亚稳相β－MoSi2随温度的升高会向α－MoSi2转变。

Structure Development during Mechanical Alloying of Mo and Si Powders

In the article, the product formation of Mo-67 at % Si powders mixture during mechanical alloying(MA) under the condition of a middle ball milling energy was studied. The mechanically alloyed powders were characterized by X-ray diffraction (XRD) and differential thermal analysis(DTA). The change in XRD patterns of the blended powders of Mo and Si during milling shows that the hexagonal (β-MoSi2) was the first phase formed under the present condition and the microcrystalline β-MoSi2 was amorphizated in the further ball milling process. The formation of tetragonal α-MoSi2 reguired much higher milling energy compared to the formation of β-MoSi2. The transformation of α-MoSi2 might take place in the milling process with the milling time increasing. DTA experiments indicated that metastable β-MoSi2 phase can transformed into stable α-MoSi2 phase with the temperature raising.