Abstract: The key technology for production of lead free-cutting steel is to control the yield of lead, the homogeneity of lead in liquid, the lead vapour pollution on environment, the surface quality of billet and smooth casting. Both controlling lead and increasing castability of steel SUM24HSL (% : ≤0.11C, 1.0-1.5Mn, ≤0.05Si, 0.04-0.09P, 0.26-0.42S, 0.25-0.32Pb) produced by 100 t EAF-LF-CC process has been studied. Results show that with adding lead 3.5-4.0 kg/1 (size 2-3 mm) at 1620-1640 °C , adding speed 50-60 kg/min, argon blowing rate 420-480 L/min, the yield of lead is 75%. Smooth casting and qualified metallurgical quality are insured by combined mold vibration parameters, suitable mold flux, casting temperature and shield casting technology.

Key words: Lead, Free-Cutting Steel SUM24HSL, Billet Continuous Casting

摘要： 铅易切削钢生产的关键技术是控制铅的收得率,铅在钢液中的均匀性,铅蒸汽对环境的污染、铸坯表面质量及顺行浇铸。从铅的控制和提高可浇铸性两方面研究了SUM24HSL钢(%:≤0.11C、1.0～1.5Mn、≤0.05Si、0.04～0.09P、0.26～0.42S、0.25～0.32Pb)的100 t EAF-LF-CC工艺。结果表明,在1 620～1 640℃加铅3.5～4.0 kg/t,铅粒度2～3 mm,加入速度50～60 kg/min,氩气流量420～480 L/min,铅的收得率为75%。匹配结晶器振动参数,合适的结晶器保护渣、浇铸温度和保护浇铸技术可保证连铸顺行和轧材冶金质量。

关键词: 铅, 易切削钢SUM24HSL, 小方坯连铸