【摘要】 对导致连铸坯中内裂纹形成的微观偏析进行了模型研究，模型中考虑了铁素体（δ）凝固向奥氏体（γ）凝固的转化以及ＭｎＳ的析出，讨论了钢中 Ｃ， Ｍｎ， Ｓ和 Ｐ对凝固过程中品间偏析、零强度温度（ＺＳＴ）、零塑性温度（ＺＤＴ）的影响结果表明，钢中碳含量对凝固前沿枝晶间的微观偏析有显著影响，碳含量在 ０．１％──０．２％之间， Ｐ的偏析显著增加， Ｓ的偏析由于受到 Ｍｎ的抑制而随碳含量变化不大；钢中 Ｐ的偏析极其严重，初始 Ｐ含量的增加显著加剧 Ｐ在枝晶间的富集；枝晶间偏析增加的同时，凝固前沿零塑性温度（ＺＤＴ）降低更多还原

【Abstract】 The micro-segregation resulting in illternal crack in continuously cast slab is studied by using a mathematical model in which the transition of ferritic/austenitic solidification and the precipitation of MnS are considered. The effects of C, Mn, S and P on the interdendritic segregation, zero strength temperature (ZST), and zero ductility temperature (ZDT) are discussed. The results show that C contellt in steel influences the ioterdendritic segregation significantly. The segregation of P increases greatly when the C content increased from 0.l% to 0.2% while that of S is not obviously changed due to the effect of Mn. P is the element with greatest segregation tendency. The segregation of P is increased with increasing initial P content. The interdendritic segregation is responsible for the decrease of zero ductility temperature (ZDT).更多还原