| Based on the Phase-field Model which is programmed in Matlab language, this paper simulates theprecipitation progress of Ni75Al14Mo11alloy. The effects of temperature and elastic energy areincorporated into the model. The simulation context is concentrated on the effect of elastic energy as topre-precipitation and effect of temperature or elastic energy as regards precipitation of γphase form γ′phase.The results are showed in the follow, in the first place, solute atoms cluster, the L10structure phaseprecipitate and then transform into L12phase(it is also called γ′phase).In the micro-structureevolution pictures, there is two kinds of L10structure. One is L10(Ⅰ) and another is L10(Ⅱ).As theelastic energy increased, the L10(Ⅰ) structure precipitation is constrained while the L10(Ⅱ) structureprecipitation is facilitated. Finally, the L10structure of two styles transform to L12structure.This paper performs micro-phase field simulation of Ni75Al14Mo11under different elastic constant,it is concluded that the precipitation of γ phasefromγ′exists in different constants and the main field forthe precipitation of γ phase from γ′is the margin of the γ′particles. That is because in the margin theatoms are easier to diffuse. It was found that the disordered phase precipitation would be acceleratedwith the increase of the elastic energy in the same time steps. In the reverse precipitation stage, theoccupation probability of Al atom at site declines with the increase of elastic energy and in the sametime step, the larger the constant is, the lower the occupation probability is. Which illustrates that theincrease of energy facilitates the γ′reverse precipitation. Nevertheless, the regularity characteristic of βand θ are not obvious. Through the analysis of result, we find Ni occupy the β, θ site mainly in thereverse precipitation stage.The changes of the temperature do not have significant affects on the γ′reverse precipitation stage,especially on the occupation probability. |
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