基于表面粗糙度对连铸钢碳当量计算方法的判断

 碳当量是连铸生产实践中分析钢种表面纵裂纹敏感性最常用的方法。为了正确判断连铸过程中钢的表面纵裂纹敏感性，基于表面粗糙度试验对比分析了合金成分和冷却速率对钢的碳当量计算结果的影响。结果表明，合金成分和冷却速率的变化改变了钢种纵裂纹敏感时的碳当量范围。根据凝固过程中冷却速率对钢种纵裂纹敏感性的影响，碳当量计算方法可分为3类，第一类适用于平衡状态下分析碳当量的Yasumoto、BSSTC和Howe公式；第二类适用于传统连铸生产时分析碳当量的Wolf、Trico、Xia和Presoly公式，其中Presoly公式的结果最为可靠；第三类适用于薄板坯连铸生产时分析碳当量的SMS公式。

Evaluation of carbon equivalent calculation of continue#br#casting steel based on surface roughness

Surface longitudinal crack susceptibility of steel grades in the continuous casting can be evaluated by using carbon equivalent，which is the most commonly method in production practice. In order to accurately identify the surface longitudinal crack susceptibility crack susceptibility of steels，the effect of alloy element contents and cooling rates on the carbon equivalent calculation of steels was analyzed based on the surface roughness experiment. The result shows that the carbon equivalent range of crack susceptibility can be changed by the alloys contents and cooling rates. The calculation methods of carbon equivalent can be divided into three categories according to the cooling rate：Yasumoto，BSSTC and Howe’s formulas suitable for the analysis under equilibrium condition；Wolf，Trico，Xia and Presoly’s formulas suitable for the traditional continuous casting，where the results of Presoly’s formula is the most reliable；SMS’s formula suitable for the thin slab continuous casting.