高碳钢小方坯二次枝晶间距与P偏析的关系

摘要

研究了高碳钢小方坯内二次枝晶间距与P偏析两者之间的关系,结果表明:P元素偏聚在二次枝晶间,二次枝晶间距较大位置处的P元素偏析率也相对较大,最大的二次枝晶间距位置和磷元素的最大偏析点均出现在柱状晶与等轴晶交界处.可以通过减小二次枝晶间距的措施,达到控制磷元素在铸坯内偏析的效果.降低拉速及在一定范围内增大二冷水比水量,能够有效的减小二次枝晶间距.%The relation between the secondary dendrite arm spacing and the segregation of phosphorus in high carbon steel billet was studied.The results showed that maximum segregation point of phosphorus in billet was in the junction of the column crystal and the equiaxial crystal.The secondary dendrite arm spacing has the same changing regularity as the segregation rate of phosphorus does in billet,so the macro-segregation of phosphorus can be controlled by decreasing secondary dendrite arm spacing.The secondary dendrite arm spacing decreases effectively by reducing the casting speed and increasing secondary cooling water flow rate in a certain range.