连铸过程结晶器内钢水凝固收缩计算研究

Study of liquid steel solidification shrinkage during continuous casting process

针对连铸结晶器铜管的锥度设计问题,采用凝固收缩——传热反馈调节计算方法,对130 mm×130 mm连铸结晶器内的传热、凝固及凝固收缩进行了计算研究,并与传统的利用假设的热流密度进行连铸坯锥度设计的计算方法进行对比。结果表明该计算方法可以有效地模拟实际连铸过程中角部区域凝固收缩对热流密度及温度分布的影响。针对CB300-V钢种,断面130 mm×130 mm连铸坯在3 m/min拉速下的计算结果为:凝固坯壳角部温度1 250℃,与经典热流公式计算的角部温度700℃有明显差别,面中心处明显的收缩开始于距结晶器上沿0.4 m的位置,凝固收缩的数值集中在0.000 2 m的范围内,角部最大收缩量为0.001 575 m。随着距表面距离的加大,凝固收缩呈减小趋势,凝固收缩的减少量与距离呈非线性关系。

The analyses of the heat transfer,solidification and solidification shrinkage in the 130 mm × 130 mm billet continuous casting process was carried out by including the solidification shrinkage-heat transfer feedback regulation algorithm,which was very important for the taper design of continuous casting mold.The effect of the solidification shrinkage on the heat flux density and temperature at the billet corner could be given out by comparing with traditional calculation method which applied the assumed heat flux density for the taper design of continuous casting mold. For CB300-V steel,cross-section 130 mm × 130 mm billet continuous casting at 3 m/min casting speed,the calculated results showed that the temperature is 1 250 ℃at the billet corner which is different from the temperature calculated by classical heat flux. The obvious solidification shrinkage at the face center begins at 0. 4 m from the mold upper edge,its value is about 0. 000 2 m,while the corner ones is about 0. 001 575 m. Solidification shrinkage decreases non-linearly with the increasing of the distance from the billet face.