基于差温轧制抗层状撕裂Q355MD-Z35特厚钢板的研究与开发  

Research and Development of Q355MD-Z35 Extra Heavy Steel Plate with Lamellar Tearing Resistance Based on Differential Temperature Rolling

作　　者：李思 孟庆勇[1] 李晓东 Li Si;Meng Qingyong;Li Xiaodong(Tangshan Iron and Steel Group Co,,Ltd.)

机构地区：[1]唐山钢铁集团有限责任公司

出　　处：《宽厚板》2025年第1期12-15,40,共5页Wide and Heavy Plate

摘　　要：抗层状撕裂特厚钢板通常拥有严格的Z向性能要求,而由于铸坯凝固偏析严重、轧制过程特厚钢板心部轧制变形渗透力差等多重因素耦合作用,极易造成特厚钢板心部组织粗大和带状组织超标等缺陷,致使特厚钢板的心部力学性能受到严重影响,特别是降低钢板的Z向性能。以碳锰钢为基体材料添加Nb、Ti微合金化元素,选择连铸凝固末端重压下连铸坯作为母材,在粗轧前3道次通过冷却设备进行高强度瞬时冷却,实现铸坯心部和表面温差250~300℃,利用差温轧制工艺生产100 mm厚度钢板,轧制后检测特厚钢板的力学性能和显微组织。结果表明:在压缩比为2.5低压缩比条件下成功开发出100 mm厚度Q355MD-Z35特厚钢板。利用连铸凝固末端重压下-差温轧制工艺生产的特厚钢板,相较于常规工艺生产的特厚钢板,其心部组织明显细化、中心偏析级别显著降低。Extra heavy steel plate with lamellar tearing resistance generally requires Z-directional properties,but due to the coupling effects of multiple factors including the severe strand solidification segregation and the poor penetra-tion of rolling deformation into the center of extra heavy steel plate during rolling,the defects of coarse microstructure and excessive banded structure at the center of extra heavy steel plate are easily caused,which severely affects the me-chanical properties at the center,especially reduces the Z-directional properties.Microalloying elements of Nb and Ti are added on the basis of C and Mn steel as the base material,the slab cast by solidification end heavy reduction tech-nique is selected as the raw material,the temperature difference from 250 C to 300 is achieved between the center and the surface of the slab by instant cooling with high intensity at the instant cooling device during the first three roug-hing passes,the mechanical properties and microstructure of the extra heavy steel plate are tested after rolling.The re-sults show that the 100 mm thickness extra heavy steel plate is successfully developed under the condition of the lower reduction ratio at 2.5.Compared with those produced by the conventional process,the extra heavy steel plate produced by continuous casting solidification end heavy reduction-differential temperature rolling technology possesses signifi-cantly refined central microstructure and remarkably reduced center segregation level.

关 键 词：特厚钢板 抗层状撕裂 凝固末端重压下 差温轧制 

分 类 号：TG1[金属学及工艺—金属学]