A Modified Cellular Automaton Model for the Quantitative Prediction of Equiaxed and Columnar Dendritic Growth

作     者：Rui Chen Qingyan Xu Baicheng Liu 

作者机构：Key Laboratory for Advanced Materials Processing Technology School of Materials Science and Engineering Tsinghua University 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2014年第30卷第12期

页      面：1311-1320页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 08[工学] 082303[工学-交通运输规划与管理] 082302[工学-交通信息工程及控制] 0702[理学-物理学] 0823[工学-交通运输工程] 

基　　金：financial support of the National Basic Research Program of China (No. 2011CB706801) the National Natural Science Foundation of China (Nos. 51374137 and 51171089) the High Technology Research and Development Program of China (No. 2007AA04Z141) the National Science and Technology Major Projects (No. 2012ZX04012-011 and 2011ZX04014052) 

主　　题：Cellular automaton Dendritic growth Crystallographic orientation Aluminum alloys 

摘      要：Since the characteristic of dendrite is an important factor determining the performance of castings, a twodimensional cellular automaton model with decentered square algorithm is developed for quantitatively predicting the dendritic growth during solidification process. The growth kinetics of solid/liquid interface are determined by the local equilibrium composition and local actual liquid composition, and the calculation of the solid fraction increment is based on these two compositions to avoid the solution of growth velocity. In order to validate the developed model, quantitative simulations of steady-state dendritic features over a range of undercooling was performed and the results exhibited good agreement with the predictions of LGK（Liptone Glicksman-Kurz） model. Meanwhile, it is demonstrated that the proposed model can be applied to simulate multiple equiaxed dendritic growth, as well as columnar dendritic growth with or without equiaxed grain formation in directional solidification of AleC u alloys. It has been shown that the model is able to simulate the growth process of multi-dendrites with various preferential orientations and can reproduce a wide range of complex dendritic growth phenomena such as nucleation, coarsening of dendrite arms, side branching in dendritic morphologies, competitive growth as well as the interaction among surrounding dendrites.