Phase-field modeling of microstructure formation during rapid solidification in Inconel 718 superalloy
Phase-field modeling of microstructure formation during rapid solidification in Inconel 718 superalloy
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DOI：
10.1016/j.actamat.2015.05.052
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发表时间：
2015-08-15
期刊：
影响因子：
9.4
通讯作者：
Emmerich, Heike
中科院分区：
文献类型：
--
作者：
Kundin, Julia;Mushongera, Leslie;Emmerich, Heike
可以使用相场建模 (PF) 来预测镍基高温合金选择性激光熔化 (SLM) 过程中的平衡和亚稳态相/晶粒形态。在本文中，通过与格林函数计算和 Kurz-Fisher 模型的理论预测进行比较，通过稳态增长问题提出并验证了二元和多组分系统的模型。通过 PF 模拟，评估了快速凝固过程中生长速度对过冷的唯象依赖性。研究发现，生长速度并未达到实际工艺和材料参数的稳态值。 PF 预测的最终微观结构与实验观察结果非常吻合。此外，模拟还提供了浓度分布，显示了溶质与枝晶核心的明显偏析。模拟的微观结构和浓度场可以用作模拟第二相沉淀的输入。 (C) 2015 Acta Materialia Inc. 由 Elsevier Ltd 出版。保留所有权利。
The prediction of the equilibrium and metastable phase/grain morphologies during selective laser melting (SLM) of Ni-base superalloys can be accomplished using phase-field modeling (PF). In this paper, a model for binary and multi-component systems is presented and validated via the steady-state growth problem by comparison to theoretical predictions of the Green-function calculations and the Kurz-Fisher model. By means of the PF simulations, a phenomenological dependency of the growth velocity on under-cooling during the rapid solidification is evaluated. It is found that the growth velocity does not achieve steady-state values for real process and material parameters. The final microstructure predicted by the PF is in good agreement with the experimental observations. Additionally, the simulations provide concentration profiles, which show a pronounced segregation of solutes to the dendrite core. The simulated microstructures and concentration fields can be used as inputs for the simulation of the precipitation of secondary phases. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.