球磨条件对MoSi_2形成的影响

EFFECT OF BALL MILLING CONDITION ON FORMATION OF MoSi 2

通过对Ｍｏ、Ｓｉ混合粉末的机械球磨，研究了不同球磨条件对ＭｏＳｉ２形成的影响。用Ｘ射线衍射仪、透射电镜和扫描电镜对不同球磨时间的粉末进行了检测与分析，结果表明，在较低球料比的条件下（１０∶１），不同转速的球磨均会使Ｓｉ固溶于Ｍｏ中，形成Ｍｏ（Ｓｉ）过饱和固溶体，但较低转速（１００ｒ／ｍｉｎ）的球磨不能发生合金化而形成ＭｏＳｉ２，只有较高转速（２２５ｒ／ｍｉｎ）的球磨才会通过机械诱发扩散固溶而逐渐形成ＭｏＳｉ２；在较高球料比的条件下（２０∶１）。

The mixture of Mo and Si powders was milled by mechanical ball milling. The effect of ball milling conditions on the formation of MoSi 2 was systematically investigated. The milled powders with various milling times were charactericed by X ray diffraction, transmission electron microscopy(TEM) and scanning electron microscopy (SEM). The results showed that ball milling results in the supersaturated solid solution of Mo(Si) under combination of low rotation speed and low ball to powder mass ratio(10∶1). MoSi 2 could only be formed under the condition of high rotation speed(225 r/min). The formation of MoSi 2 during mechanical alloying was characterized by diffusion and solid solution. On the other hand, MoSi 2 was formed via the mechanically induced self propagating reaction under condition of high ball to powder mass ratio(20∶1).