Abstract: The Nb-Ti microalloying undersea linepipe   steel   HSL450S(0.06C,0.40Cr,0. 15Mo,0.02Ti,0.05Nb) has been developed by 90 t EBT arc funace- 100tLF+VD-wire feeding - Φ220 mm CC flow sheet.It was obtained by analyzing  30  heats  that  [O]  was 35.2×10^-6 and [N] was78.8×10^-6.The  structure  of  steel  was  tempered  bainite-pearlite  +  polygonal  ferrite. The  mechanical  properties  of  Φ102  mm×14  mm  and  Φ168.3  mm×8.7  mm  tube  of  steel HSL450S with grain size rating 10～11 met the requirement of standard of for undersea linepipe steel X60 and X65 grade.

摘要： 通过90t EBT电弧炉-100 t LF+VD-喂丝-Φ20mm CC流程开发了Nb-Ti微合金化海底管线管钢HSL450S(%:0.06C、0.40Cr、0.15Mo、0.02Ti、0.05Nb)。经30炉分析得出,[O]为35.2×10^-6,[N]为78.8×10^-6。该钢的组织为回火贝氏体-珠光体+多边形铁素体。轧制的Φ102mm×14mm和Φ168.3mm×8.7mm HSL450S钢管的晶粒度为10～11级,机械性能满足海底管线管X60、X65钢级标准要求。

关键词: EAF-LF+VD, Nb-Ti微合金化, 海底管线管钢, 开发