PHASE FIELD SIMULATION OF POLYCRYSTALLINE SOLIDIFICATION IN BINARY ALLOYS

摘要：

A phase field model for polycrystalline solidification in binary alloys is developed, which takes into account the arbitrary crystallographic orientation and preserves the rotational invariance of the free energy. Stochastic nucleation is incorporated into the phase field model through a Poisson seeding algorithm and calculation of nucleation kinetic for binary alloys. Equiaxed dendritic solidification in isothermal system and the columnar-to-equiaxed transition (CET) in cooling system are simulated by the phase field model. The transformation kinetic of isothermal solidification proceeding via nucleation and subsequent dendritic growth is studied and compared with the JMAK theory, the blocking effect is clearly shown by the results. In the constant cooling system, the selection of columnar grain and the CET are nicely reproduced, and it is found that the columnar zone length and the equiaxed grain size increase with the cooling rate, which results from the competition between nucleation and growth.

关键词： Phase field model Solidification Nucleation Binary alloys

作者: Junjie LI Jincheng WANG Gencang YANG

作者单位: State Key Laboratory of Solidification Processing, Northwestern Polytechnical University Youyi Road 127 Xian, 710072, China

会议类型: 国际会议

会议名称: 第七届环太平洋铸造及凝固过程模型化国际会议(The 7th Pacific Rim International Conference on Modeling of Casting and Solidificetion Process(MCSP7-2007))

会议地点: 大连

会议语种:英文

页码: 241-248

在线出版日期: 2007-08-19（万方平台首次上网日期，不代表论文的发表时间）