100t LD-LF-RH-CC流程冶炼60Si2Mn弹簧钢非金属夹杂研究  

Study on Nonmetallic Inclusions in Spring Steel 60Si2Mn Produced by 100 t LD-LF-RH-CC Flow Sheet

作　　者：刘飞 岳峰 刘佳伟 肖波[3] 翟万里[3] Liu Fei;Yue Feng;Liu Jiawei;Xiao Bo;Zhai Wanli(Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Beijing 100083;School of materials science and engineering,University of Science and Technology Beijing,Beijing 100083;Chief Engineer Office,Huaigang Special Steel Co Ltd,Jiangsu Shagang Group,Huai'an 223002)

机构地区：[1]北京科技大学钢铁共性技术协同创新中心,北京100083 [2]北京科技大学材料科学与工程学院,北京100083 [3]江苏沙钢集团淮钢特钢股份有限公司总工办,淮安223002

出　　处：《特殊钢》2020年第4期15-18,共4页Special Steel

摘　　要：试验60Si2Mn弹簧钢(/%:0.58C,1.75Si,0.75Mn,0.012P,0.005S,0.006Als,0.008Alt)的工艺流程为100 t转炉不加铝饼脱氧,采用硅铁脱氧,控制终点[C]≥0.08%,出钢温度1 620~1 660℃,LF到站温度≥1 500℃,精炼时间不少于35 min,RH真空度≤100 Pa并且保持时间≥20 min,软吹前喂入硅钙线100 m进行变性夹杂物处理,150 mm方坯采用全程保护浇铸。分析结果表明,钢中氧含量在RH精炼过程中到达最低,在中间包阶段又有所回升。在LF精炼中,钢液增氮明显。夹杂物成分以Al2O3、SiO2、MgO和CaO为主,在LF精炼过程中,SiO2含量下降了26.7%,MgO和CaO含量上升了36.7%,最终铸坯中夹杂物成分为33%Al2O3,20.7%SiO2,45%MgO和CaO,减少了钢中高硬度夹杂物的含量。The production process of tested spring steel 60 Si2 Mn(/%:0.58 C,1.75 Si,0.75 Mn,0.012 P,0.005 S,0.006 Als,0.008 Alt)is not adding aluminum cake but adding ferrosilicon to deoxidize in an 100 t converter,controlling end[C]≥0.08%,and tapping liquid temperature 1 620~1 660 ℃,LF original temperature≥1 500℃,refining time no less than 35 min,RH vacuum≤100 Pa for≥20 min,feeding 100 meters of calcium and silicon wire for modification of inclusions before soft blowing,in whole process shielding-atmosphere casting 150 mm square billet.Analysis results show that the oxygen content in steel reaches the lowest in RH refining process,and rises in tundish stage.In LF refining process,the nitrogen increase of liquid steel is obvious.Inclusions are mainly composed of Al2 O3,SiO2,MgO and CaO.During LF refining,the content of SiO2 decreases to 26.7%,while the content of MgO and CaO increases to 36.7%.Finally,the inclusions in the casting billet are 33% Al2O3,20.7% SiO2 and 45% MgO and CaO to decrease the high hardness inclusions in steel.

关 键 词：100 t LD-LF-RH-CC流程 弹簧钢60Si2Mn 夹杂物 尺寸 成分 

分 类 号：TF762.5[冶金工程—钢铁冶金]