Fe-Mo合金的时效析出行为

Precipitation Behaviour in Fe-Mo Binary Alloys

用 X 射线、电子衍射及透射电镜观察等方法研究了 Fe-27Mo 及 Fe-16Mo 合金的时效析出行为.结果发现,在873～1453K 时效时.时效初期,两种合金中均有一种新的过渡相——R 相析出.随时效进行,过渡相 R 将向平衡相μ(1213～1453K)或 Laves(873～1213K)转度.过渡相 R 为菱形点阵,点阵常数α=0.8977nm,α=74.4°,其 Mo 含量为48%,呈棒状或块状形态析出.时效初期由于过渡相 R 的析出引起合金硬化.

The precipitation behaviour in supersaturated Fe-27Mo and Fe-16Mo alloys during aging is studied mainly by means of X-ray diffraction and transmission electron microscopic observation.A metastable R-phase is precipitated in the early stage of aging at 873-1453K in both Fe-27Mo and Fe-16Mo alloys.In the later stage,the metastable R-phase is transformed to equilibrium phases—μ-phase at 1213-1453K and Laves-phase at 873-1213K respectively.The crystal structure of the metastable R-phase is rhombohedral lattice with parameters:α=8.977(?),, α=74.4°.The result of chemical analyses shows that the Mo content in the metastable phase is about 48%.The metastable R-phase is precipitated with a rod-shaped or a globular morphology. And with the precipitation of the R-phase the hardness of the alloys is increased.