摘要
对绝大多数管线钢来说,氮是有害元素,钢水中氮含量偏高会使钢产生应力时效,降低管线钢的成型性及高温韧性、塑性和焊接性能。介绍了电炉冶炼高端管线钢钢水中氮元素来源,主要为废钢原料含氮不稳定以及电弧区钢液容易吸氮,并通过冶炼工艺的比对,对电炉不同钢渣性能、不同铁水比例、冶炼时熔池流场对N含量的影响进行了分析,找出控制电炉钢水氮含量的有效途径,主要有提高电炉钢渣性能、合理的铁水配比、电炉底吹CO2气体、精炼、连铸防二次增N工艺等,工艺改进后氮含量平均控制在8×10^-5以下。
Nitrogen is a harmful element for most pipeline steels.High nitrogen content in molten steel will cause stress aging,and reduce the formability,high temperature toughness,plasticity and weldability of pipeline steels.This paper introduces the source of nitrogen element in molten steel of high-end pipeline in EAF smelting.The main reasons are unstable nitrogen content of scrap steel and easy nitrogen absorption of molten steel in arc zone.Through comparison of smelting processes,the effects of different slag properties,molten iron ratio and flow field of molten pool on nitrogen content in EAF are analyzed.The effective ways to control nitrogen content in molten steel of EAF are found out,mainly improving nitrogen content in EAF.The average nitrogen content of slag,molten iron ratio,bottom blowing CO2 gas,refining and continuous casting process is controlled below 8×10^-5 after process improvement.
作者
王学义
宋智宇
WANG Xueyi;SONG Zhiyu(Tianjin Pipe(Group)Corporation,Tianjin 300301,China)
出处
《工业加热》
CAS
2019年第6期14-16,共3页
Industrial Heating
关键词
管线钢
低氮钢
工艺改进
pipeline steel
low nitrogen steel
technology improvement
