摘要
用元胞自动机(cellular automaton,CA)方法模拟凝固组织,采用有限差分方法(FDM)模拟凝固过程中的热传导、溶质扩散及动量传输等宏观传输过程,将二者耦合(CA-FDM)模拟了钢锭凝固过程中晶粒的形核与生长过程,预测了表面柱状晶的长度、取向及柱状晶-等轴晶的转变,模拟结果表明,形核率与生长速度的比值是决定组织形态(包括晶粒形貌、柱状晶-等轴晶转变)的重要因素,合理地控制两者的比值可以获得优良的微观组织,为使这种方法实用化,以增加可模拟元胞的数目,在开发程序时使用了虚拟内存分配技术。
Cellular automaton (CA) was used in simulating the microstructure evolution during solidification, and finite difference method (FDM) was used in solving the conservation equations for heat transfer, solute transfer and momentum transfer which govern the macro-transport phenomena during solidification. Coupling of CA with FDM (CA-FDM) could predict the microstructure evolution under varied solidification conditions, including the length of the columnar grains and the columnarto-equiaxed transition (CET). It was found that the ratio of nucleation rate and growth rate is essential to the morphology formation and CET. To maximize the number of the simulated cells, the virtual memory allocation technique was adopted.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2004年第5期452-456,共5页
Acta Metallurgica Sinica
基金
国家高技术研究发展规划资助项目 2001AA339030
关键词
元胞自动机
凝固组织
宏观传输模型
cellular automaton
solidification microstructure
macro-transport model
