100t LF Si-Ca脱氧低铝锅炉管用钢15CrMoG夹杂物分析  

Analysis on Inclusions in Low Aluminium Steel 15CrMoG for Boiler Pipe Refining in 100 t LF by Si-Ca Deoxidation

作　　者：吴明洋 

机构地区：[1]山东钢铁股份有限公司莱芜分公司特钢事业部,莱芜271105

出　　处：《特殊钢》2018年第1期65-67,共3页Special Steel

摘　　要：高压锅炉管用钢15CrMoG(/%:0.12~0.18C,0.17~0.35Si,0.40~0.70Mn,≤0.015P,≤0.015S,0.80~1.10Cr,0.40~0.55Mo,≤0.020Alt)的生产工艺流程为60%铁水+优质废钢-100 t UHP EAF-LF-VD-Φ500mm坯连铸-轧制。通过电弧炉出钢Al-Si预脱氧,LF精炼Si-Ca脱氧,优化精炼渣系的组成为(/%):55~60CaO,30~35Al_2O_3,5~10SiO_2,(CaO)/(Al_2O_3)=1.41~1.74,精炼后钢水中的Alt为0.011%~0.014%。Φ140 mm和Φ160 mm热轧材的夹杂物分析结果表明,钢中夹杂物中MnS为10%,铝酸钙为75%,SiO_2 7.5%,含Ti氧化物5%,其它2.5%,钢中≤5.0μm夹杂物占95%以上,满足锅炉管用钢15CrMoG的技术要求。The production process flowsheet of steel 15CrMoG for high pressure boiler pipe （/% ： 0. 12 -0. 18C, 0.17 - 0. 35Si, 0.40 -0.70Mn,≤0. 015P, ≤0.015S, 0. 80 -1.10Cr, 0. 40 - 0. 55Mo, ≤0.020Alt） is 60% hot metal ＋ quality scrap- 100 t UHP EAF-LF -VD-dP500 mm bloom casting-roiling. With A1-Si pre-deoxidation in EAF tap- ping, Si-Ca deoxidation in LF refining, and using optimized refining slag （/%） ： 55 - 60CaO, 30 -35A12O3,5 - 10SiO2, （CaO）/（Al2O3） = 1.41 -1.74, the Alt content in refined liquid is 0. 011%-0. 014%. The analysis results on inclu- sions in Ф140 mm and qbl60 mm hot rolled products show that the ingredient of inclusions in steel is 10% MnS, 75% calci- um aluminate, 7.5% SiO2, 5% oxide containing Ti, and 2. 5% others, and the ≤5 μm inclusions make up more than 95% of the total mount of inclusions in steel to meet the technical requirement of steel 15CrMoG for boiler pipe.

关 键 词：高压锅炉管用钢15CrMoG EAF—LF—VD-Ф500 mm坯连铸低铝Si—Ca脱氧夹杂物 

分 类 号：TF777[冶金工程—钢铁冶金] TG142.1[一般工业技术—材料科学与工程]