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基于微观相场动力学模型,研究沉淀早期不同成分Ni-Al-V合金时效时有序相的生长和组织生长方向的变化。结果表明:沉淀早期有序相间的竞争生长会很大程度地影响合金的形貌及生长方向。在一定的温度、应力场作用下,Al含量较低时,DO22有序相先析出,DO22相颗粒数量较多、尺寸较小,有序相的筏化不明显,合金整体上无显著的筏化现象;Al含量稍高时,L12相先析出,DO22相颗粒数量较少、尺寸较大,组织在[010]方向上发生一定程度的择优生长;Al含量较高时,L12相先析出,DO22相颗粒数量继续减少、尺寸继续增大,组织在[100]方向上显示出较强的筏化趋势;较低温度时效的合金L12有序相析出提前,组织的筏化趋势较弱。
Based on the microscopic phase field kinetics model, the growth of ordered phases and the change of the growth direction of the microstructures were studied during aging of Ni-Al-V alloys with different compositions. The results show that: the early phase of precipitation competitive growth phase will greatly affect the morphology and growth direction of the alloy. Under the action of certain temperature and stress, when the content of Al is low, the ordered phase of DO22 is first precipitated, the number of DO22 phase particles is larger, the size is smaller, the rafting of ordered phase is not obvious, and there is no obvious raft When the content of Al is slightly higher, the L12 phase first precipitates, the number of DO22 phase particles is smaller and the size is larger, and some preferred growth occurs in the direction of [010]. When the content of Al is higher, The number of DO22 phase particles continued to decrease and the size continued to increase. The microstructure showed a strong tendency of rafting in the [100] direction. The lower temperature aging alloy L12 precipitated in advance, and the tendency of the organization was weaker.