SWRH82B盘条芯部马氏体的质量改进

Quality Improvement for Central Martensite of SWRH82B Wire Rods

SWRH82B盘条芯部马氏体的形成主要是由于铸坯中C、Mn、Cr元素中心偏析造成在Stelmor控冷中CCT曲线右移而引发马氏体转变。通过优化连铸工艺减少方坯偏析指数,并根据CCT相变曲线对Stelmor控冷工艺进行了优化,显著减少甚至消除了芯部马氏体,盘条质量明显提高。

The formation of central martensite in SWRH82B wire rods is mainly attributed to the central segregation of C,Mn and Cr in billet during casting process.The segregation causes phase transformation delay of CCT curves which leads to martensite transformation.The central martensite can be remarkably reduced and even eliminated due to the decreased central segregation index in billet in virtue of optimizing casting process,and to the optimized Stelmor controlled cooling process based on the CCT curves.Thus,the quality of SWRH82B wire rods can be greatly improved.