板坯连铸凝固过程中的自由热收缩行为

根据钢铸态热膨胀特性及实际过程中钢的连铸工艺特点，建立基于凝固传热与自由热收缩耦合的自由热收缩有限差分计算模型。利用该模型系统研究了铸坯自由热收缩行为沿铸流上的分布以及不同钢种之间凝固自由热收缩行为。研究表明，铸坯在中心全液相、两相和全凝固阶段表现的自由热收缩行为呈现不同规律；不同钢种的凝固自由热收缩量沿拉坯方向上的分布也相应存在差异。该模型可为制定不同钢种和断面的连铸辊缝控制工艺与轻压下工艺提供理论依据。

Free thermal shrinkage behavior during the solidification process in slab casters

Based on the thermal expansion properties of cast steels and continuous casting process condition,the fi-nite difference method for thermal transform and free thermal contraction of slabs was developed for prediction of the thermal field distribution and free thermal contraction behavior.The results show that the free thermal con-traction along the strands has different behaviors in different solidification stages,and the different effects of steel carbon content on the free thermal contraction are also found.A theoretical foundation to the roll gap control tech-nique and soft reduction process for different steel grades and casting cross sections can be provided.