连铸坯凝固过程热力耦合有限元模拟

来源期刊：钢铁2009年第3期

论文作者：陈永 罗歆 沈厚发

文章页码：36 - 39

关键词：大方坯连铸； 结晶器； 传热； 热-力变形； 有限元法

Key words：continuous bloom casting； mold； heat transfer； thermo-mechanical deformation； finite element method

摘    要：以铸坯和结晶器之间的间隙热阻为纽带,考虑保护渣凝固对接触热阻和渣膜热阻的影响,建立了连铸结晶器与铸坯热力耦合模型并编写了相应的有限元仿真程序。模型预测的坯壳厚度和实验结果吻合良好,两者差值≤2 mm。应用模型分析了大方坯连铸结晶器内的传热过程和坯壳的应力分布。结果表明,随着拉速提高,凝固坯壳厚度减薄,铸坯产生角部裂纹的趋势增加。

Abstract: A thermo-mechanical finite element model was established to analyze the heat transfer from mold to strand and stress distribution in strand based on the air gap resistance between solidified shell and mold by considering the influence of the mold flux on the thermal resistance among the strand,the flux film and the mold.The calculated strand shell thicknesses agreed well with the measured with a difference within 2 mm.The heat transfer in the mold and stress distribution in the bloom at different casting speeds were obtained by using the model.It was shown that when the casting speed was increased from 0.7 m/min to 0.9 m/min,the strand temperature became higher and the solidified shell thickness became thinner,which increased the cracking risk near the strand corners.