Investigation of Interaction Between Dendritic Crystal Growth, Microporosity Formation, and Melt Convection on Micro and Macroscales

该建议涉及模型和实验研究铸件中的微孔。 我们的目标是了解微观结构的形成是如何影响的微孔生长和对流的合金液相。 提出了三项不同的任务。 第一种是采用相场法模拟枝晶生长、微孔形成和熔体流动之间的相互作用。 这些结果将被耦合到一个宏观模型预测微孔成核，生长，团聚和迁移。 最后，将在橡树岭国家实验室进行实验，为验证预测提供数据。 如果成功，这项研究将有助于对微孔形成的基本理解。 待开发的计算机代码可由商业铸造代码开发者使用，以提高关于凝固过程的这一重要要素的建模能力。 本奖项将集中在微观孔隙形成的微观尺度建模和开发的方法，将这个模型与宏观模型相结合。 还将进行验证实验的规划，预计未来将与ORNL进行广泛的合作。

The proposal deals with models and experiments to study microporosity in casting. The goal is to understand how microstructure formation is influenced by microporosity growth and convective flow of an alloy liquid phase. Three distinct tasks have been laid out. The first is to use a phase field method to simulate the interaction among dendritic growth, microporosity formation and melt flow. These results will be coupled into a macroscopic model for predicting microporosity nucleation, growth, agglomeration, and migration. Finally, experiments will be conducted at Oak Ridge National Laboratory to provide data for validation of the predictions. If successful, the research will contribute to the fundamental understanding of microporosity formation. The computer codes to be developed could be used by commercial casting code developers to improve the modeling capability with respect to this important element of solidification processing. The present award will concentrate on the microscale modeling of microporosity formation and on developing the methodology for coupling this model with a macroscopic model. Planning for validation experiments will also be carried out, in anticipation of a future extensive collaboration with ORNL.