板坯结晶器传热与变形的非均匀性

结晶器的传热和变形是导致连铸坯表面缺陷及裂纹的重要因素。基于宽厚板连铸结晶器在线监控系统实测数据，建立针对实测温度的结晶器传热反问题模型，反算迭代结晶器铜板的热流与温度分布，以此为基础，将反算热流和温度施加于热-弹塑性力学模型，模拟和分析实际浇注过程中铜板传热与变形的分布特征。结果表明，结晶器温度分布呈现出明显的非均匀性，传热沿浇注方向体现出继承倾向。铜板的最大变形在宽面中心附近，变形沿中心向两侧角部逐渐减小。浇注过程中，铜板宽度方向上的变形与温度分布趋势接近，并随着电偶实测温度的波动而变化。将实测与模拟相结合的数值分析方法，能够如实反映结晶器过程的非均匀特征，为预测裂纹、优化工艺等提供借鉴和参考。

Non-uniformity of Mould Heat Transfer and Distortion During Wide and Thick Slab Continuous Casting

Heat transfer and distortion of mould plates have a great impact on surface defects and cracks. Based on the measured data of online monitoring system for wide and thick continuous casting mould, the inverse mathematical model for mould heat transfer is built, in which the distribution of heat flux and temperature of mould plates is calculated from the measured temperatures. Through applying the inverse simulation results on the thermo-elastic-plastic model, the thermal behavior and distortion of mould plates are further investigated. The results indicate the distribution of mould temperature takes on a notably non-uniform characteristic and has an inherited tendency along the casting direction. Maximal distortion appears at the center area in wide faces, and decreases gradually towards slab corners. Along the width direction, plate distortion has the same trend with the profiles and fluctuations of mould temperatures. The analysis methods through combination of online measurement data with numerical simulation can reflect the non-uniform characteristics of mould process, and provide reliable basis for prediction of surface defects and process optimization.