The Grain Structure of Castings

本研究采用实验和建模方法， 铸件中等轴晶体的形核。 在模型中， 晶体被假定为从枝晶碎片成核，并且 因此，该模型被认为比 迄今为止采用的半经验非均质成核模型。 本研究计划包括：（1）使用透明水性 （2）模拟以证实模型的基础;（3）检查 实验室规模的金属铸件，看看模型是否可以 合理外推;（3）晶粒结构研究 作为模型的最终测试。 %%% 这个程序链接到真实的铸造实践的基本方法 通过开发改进的柱状预测模型， 等轴晶粒转变以及等轴晶粒尺寸和尺寸 分布 这一主题对于精确建模 铸件的晶粒组织

This research incorporates an experimental and modeling approach to the nucleation of equiaxed crystals in a casting. In the model the crystals are assumed to nucleate from dendrite fragments, and therefore the model is considered to be more realistic than the semi-empirical heterogeneous nucleation models employed heretofore. This research plan includes: (1) the use of a transparent aqueous analogue to substantiate the basis of a model; (2) examination of laboratory scale metallic castings to see if the model can be extrapolated with justification; and (3) study of grain structures in continuously cast steel as an ultimate test of the model. %%% This program links a fundamental approach to real foundry practice by developing improved predictive modeling of the columnar to equiaxed grain transition and the equiaxed grain size and size distribution. This subject is critical to accurate modeling of the grain structure of castings.