Yongsheng LI
材料科学技术(英文)
The interphase boundary evolution of ordered phase in Ni75AlxV25-x alloy during precipitation was simulated on atomic-scale based on the microscopic phase-field dynamic model. The results show that the second phase precipitated from the interphase boundary formed by the first phase and the disordered matrix at high temperature, and from the interphase boundaries of the first phase at low temperature. L12 phase had obvious selective orientation when precipitated from the interphase boundaries of D022. L12 phase nucleated easily at the interphase boundaries formed by [10] and [01] directions of D022 projection along [001] direction, and grew easily at [10] direction. There was no the selective orientation when L12 phase precipitated from the interphase boundary formed by D022 and the disordered matrix. D022 phase had the selective orientation when precipitated from the interphase boundaries of L12, and grew along the [10] direction.
关键词:
Microscopic phase-field
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Yongsheng LI
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Zheng CHEN
材料科学技术(英文)
The interrupted aging mechanisms were applied to Ni75Al2.9V22.1 alloy by using the microscopic phase-field simulation method. For the single phase region existing at high temperature, the low content alloy was used as the study object. With the progressive aging mechanisms, the metastable phase γ' of high temperature can be obtained from the low temperature two phase regions, and the quantity of γ' phase reduces with increasing temperature. The θ single phase morphology at high temperature regions will turn to be the γ'+θ two phase morphology at low temperature with the interrupted aging method. Despite of the different precipitation paths of γ' phase, the precipitation mechanisms are the same for the low temperature aging and high temperature interrupted aging.
关键词:
Microstructure
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