LF-VD工艺冶炼20CrMnTi齿轮钢全氧和夹杂物控制研究  

Study on Total Oxygen and Inclusion Control of 20CrMnTi Gear Steel by LF-VD Process

作　　者：陈正权 Chen Zhengquan(Sansteel Minguang Iron and Steel Group Co.,Ltd.,Sanming Fujian 365000)

机构地区：[1]福建三钢闽光股份有限公司技术中心,福建三明365000

出　　处：《山西冶金》2019年第6期24-27,共4页Shanxi Metallurgy

摘　　要：对福建三钢转炉-LF精炼-VD精炼-连铸工艺生产的20CrMnTi齿轮钢全氧和夹杂物行为研究,发现VD终渣中w(FeO)增加0.1%,全氧含量(质量分数)增加1×10-6左右;VD终渣碱度R在6~18范围内时,R与全氧之间没有明显的对应关系;VD终渣m(CaO)/m(Al2O3)在1.5~1.8范围内,钢中全氧较低,且夹杂物塑性较好。认为合理渣系中从(FeO)小于1%,m(CaO)/m(Al2O3)的比值在1.5~1.8,渣中的R控制在8~10之间。由于钢液S含量和喂入Ca-Si线偏高导致夹杂物中CaS含量偏高。当Al活度为0.03%、0.04%和0.05%,Ca活度大于0.0012%,0.0014%和0.0017%,S的活度小于0.011%、0.009%和0.007%时,钢液中可以形成低熔点钙铝酸盐12CaO-7Al2O3,且抑制CaS的形成。The full oxygen and inclusion behavior of 20 CrMnTi gear steel produced by converter-LF refining-VD refining-continuous casting process was studied.It was found that the content of FeO in VD final slag increased by0.1%,and the content of total oxygen increased by about 1×10-6.When the basicity R of VD final slag was within the range of 6~18,there was no obvious correspondence between basicity R and total oxygen.Wh CaO/Al2 O3 of the VD final slag was within the range of 1.5~1.8,the total oxygen in the steelwas low.and the plasticity ofthe inclusionwa good.It is considered that the FeO content was less than 1%in reasonable slag system,the CaO/Al2 O3 ratio was1.5~1.8 in reasonable slag system,and the basicity in slag system was controlled between 8 and 10 in reasonable slag system.Due to the high content of S in the molten steel,the CaS content in the inclusion was on the high side.When the activity of Al was 0.03%,0.04%and 0.05%,the activity of Ca was greater than 0.0012%,0.0014%and 0.0017%.When the activity of S was less than 0.011%,0.009%and 0.007%,low melting point calaluminate 12 CaO-7 Al2 O3 can be formed in molten steel,and the formation of CaS was inhibited.

关 键 词：20CrMnTi 齿轮钢 全氧 夹杂物 热力学 

分 类 号：TF777[冶金工程—钢铁冶金]