邢钢低碳400系铁素体不锈钢AOD控氮工艺实践

在低碳400系不锈钢中,氮能恶化晶间腐蚀、低温冲击韧性、缺口敏感性和焊接等性能。因此,在低耗、高效前提下降低其氮含量成为AOD冶炼中的重要课题。结合生产试验,通过探讨回归分析法在其吹氩脱氮工艺控制中的应用,结合脱氮的热力学计算对AOD生产实践数据的分析,由拟合方程确定的AOD冶炼410S不锈钢和低碳430不锈钢时氮氩切换点为吹氮450m³时切换氩气,410S不锈钢正常冶炼时一般吹氩量控制在1550m³,低碳430不锈钢AOD吹氩量一般控制在2050m³时可以将AOD终点氮含量控制在0.009 0%以下,并降低氩气消耗。

AOD Nitrogen Control Pratice of of Low Carbon 400 Series Ferritic Stainless Steel at Xingtai Iron and Steel

 Nitrogen can deteriorate intergranular corrosion, low temperature impact toughness, notch sensitivity and soldering properties of low carbon 400 series stainless steel. Therefore, reducing the nitrogen content under the premise of low consumption and high efficiency has become an important issue in AOD smelting. Combined the production test, by exploring the application of regression analysis in the control of argon-denitrification process and combined with the thermodynamic calculation of denitrification to analyze the production data of AOD, it is determined by the fitting equation that the switching point of nitrogen to argon is at blowing nitrogen 450 m³ ,the normal blowing argon amount of 410S stainless steel in AOD is controlled at 1550m³, and the blowing argon amount of low carbon 430 stainless steel in AOD is generally con¬trolled at 2050m³ to get controlled N] below 0.0090% and reduce of argon consumption.