反向凝固连铸碳素钢带中复合层的凝固生长规律

Thickness Variation of 08Al Clad Layer during Inversion Casting Process

在实验室条件下 ,用市售碳素钢板作为母带 ,用 0 8Al低碳钢作为复合层材料 ,对反向凝固连铸薄带生产过程中复合层在母带表面的凝固生长规律进行了研究。研究结果表明 ,母带在钢水中的浸渍时间、母带厚度和钢水过热度对复合层厚度有显著影响 ,而且这些工艺参数之间存在交互作用 ;复合层的变化经历了“快速生长”、“平衡相持”和“迅速回熔”三个阶段 ,这三个阶段在复合层厚度 -浸渍时间图上共同组成具有较长平台的反向凝固“∩”形特征曲线 ;较低的钢水温度和较厚的母带有利于增加复合层厚度。

The regulation of 08Al steel clad layer solidified on the surface of 15F mother sheet was investigated detailedly under laboratory conditions. The hot rolling 15F strips with nominal thickness of 1.2 mm, 1.5 mm and 2.0 mm were used for mother sheet and the steel type 08Al was used for clad material crystallized on to the mother sheet. The experimental results showed that the thickness of clad layers were remarkably influenced by three process parameters, i.e., thickness of mother sheet, superheat degree of liquid steel and the dipping time when mother sheet was immerged into liquid steel. With regard to the effect of process parameters on the growth of clad layer, interactions between the parameters also were found in the experiment. The experimental results also showed that the growth of newly solidified layer sequentially goes through three stages: rapidly growing stage, steady equilibrium stage and quickly remelting stage with the increasing of immersion time for mother sheet dipping in melt. On the plot of clad layer thickness versus immersion time, the three stages of clad layer growth composed a ‘∩’ curve with a long platform in the middle. Additionally, lower melt temperature and thicker mother sheet were propitious to the growth of clad layer.