Abstract: The production process flowsheet for developed gear steel 20CrMnTiH with narrow hardenability band is metal pre~desulphurizalion-130t BOF-LF-RH-280 mm x 280 mm bloom casting-rolling to Φ60 mm round bar. With designed interior composition (/% : 0.18 ~ 0.20C, 0.20 ~ 0.30Si, 0.90 〜0.98Mn, ≤0. 025P, ≤0. 010S, 0.05 ~ 0.07Ti,≤0.0015O) , setting mold electromagnetism stirring parameters 200A, 2.5Hz, controlling casting speed 0.62 m/min, liquid superheating extent 15〜30 °C , the examination results show that the chemical composition is stable, the oxygen content in steel ≤1.3 x 10^-6, the rating of nonmetallic inclusions ≤1.0, the rating of banding structure ≤2.0 and the AHRC value of hardenability band ≤3.5 to meet the requirement of products specification.

Key words: Gear Steel 20CrMnTiH, Narrow Hardenability Band, 130t BOF-LF-RH-280mm x 280mm Bloom Casting, Product Development

摘要： 开发的窄淬透性带20CrMnTiH齿轮钢的生产工艺流程为铁水预脱硫-130t BOF-LF-RH-280mm×280mm坯连铸-轧制至Φ60mm圆钢。通过设计的内控成分（/%:0.18~0.20C，0.20~0.30Si，0.90~0.98Mn，≤0.025P，≤0.010S，0.05~0.07Ti，≤0.0015O），设立结晶器电磁搅拌参数200A,2.5Hz，控制拉速0.62m/min，过热度15~30℃。检验结果表明,化学成分稳定,钢中氧含量≤11.3×10^-6，非金属夹杂级别≤1.0，带状组织级别≤2.0,淬透性带宽HRC值≤3.5,满足产品协议要求。

关键词: 20CrMnTiH齿轮钢, 窄淬透性带, 130t BOF-LF-RH-280mm x280mm坯连铸, 产品开发