摘要
采用元胞自动机法(CA)计算铸锭的凝固组织,围绕宏观偏析的宏/微观耦合计算问题,针对微观组织模型的选取,本文从元胞尺度为介观(100μm×100μm)和微观(10μm×10μm)两个方面,以Al-4.7wt%Cu合金铸锭为例,分别从1能否计算出柱状晶向等轴晶转变(CET)过程;2能否计算出生长过程的二次枝晶;3能否较准确计算出晶粒的溶质分布情况;4计算效率快慢等四个方面对元胞自动机模型中的KGT模型和溶质扩散性模型进行了对比计算。结果发现,溶质扩散性模型在计算二次枝晶生长及溶质分布情况等方面有绝对优势,但其计算效率相比较而言仍待提高。
The solidification process of the ingot was calculated using cellular automata （CA）, focusing on the selection of the microstructure models which can be combined into the macro/micro model in macro-segregation calculation, taking a small amour of A1-4.7wt%Cu ingot as an example, the comparison of two CA model, KGT model and solute distribution model was made under two cell scale （one is 100μm×100μm, and another is 10μm×10μm from four aspects： （1） whether CET process is showed or not？ （2） whether second dendrite arm of growth process is displayed or not？ （3） whether solute distribution is accurately calculated or not？ （4） Is the calculation efficiency accepted or not？ The simulation and experiment results show that the solute distribution model has absolute advantage in second dendrite arm and the solute distribution is the fit model, however, its calculation efficiency is supposed to be improved.
出处
《热加工工艺》
CSCD
北大核心
2015年第21期72-76,共5页
Hot Working Technology
基金
国家重点基础研究发展计划资助的课题(2011CB610402)
国家自然基金(51475138)
