QP钢板坯角部气泡缺陷成因与调控  

Cause analysis and improvement of bubble defects in corners of QP steel

作　　者：胡暑名[1] 常文杰[1] 丁占元[1] 田晨 袁磊 HU Shu-ming;CHANG Wen-Jie;DING Zhan-Yuan;TIAN Chen;YUAN Lei(Steelmaking Plant,Baoshan Iron and Steel Co.,Ltd.,Shanghai 201900,China;School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China)

机构地区：[1]宝山钢铁股份有限公司炼钢厂,上海201900 [2]东北大学冶金学院,辽宁沈阳100819

出　　处：《中国冶金》2023年第3期132-136,共5页China Metallurgy

基　　金：国家自然科学基金资助项目(52174302)。

摘　　要：QP钢作为典型的第3代汽车板用钢,其连铸板坯角部常存在气泡缺陷,进而影响产品质量。通过对现场生产QP钢板坯角部气泡缺陷取样分析以及气体生成热力学计算,明确了QP钢生产过程中角部气泡缺陷的形成原因与机理。研究结果表明,角部气泡大部分为圆形且尺寸较大的氩气泡,少部分为尺寸较小的氮气泡,并排除了CO气泡的存在。在此基础上,通过降低钢液中氮含量、提高钢液过热度、适量降低吹氩流量等优化措施,成功改善并降低了气泡缺陷发生率。经优化,QP钢板坯角部气泡缺陷发生率已由6.62%降低至2.45%,有效地确保了生产的稳定性。As a typical third generation of the automobile steel, the corner defects of continuous casting slab of QP steel often exist, which affect the product quality. In order to define the causes and formation mechanism of bubble defects in corners of QP steel during continuous casting process, both the bubble defects sampling of QP steel slab produced on site and gas generation thermodynamic calculation were analyzed. The results show that a large number bubbles defects are formed by Ar which are circular and have large size, a few are N2bubbles with small size, and the existence of CO bubbles is excluded. On this basis, by reducing the N content in molten steel, increasing the superheat of molten steel, and appropriately reducing the Ar blowing flow, the incidence rate of bubble defects has been successfully reduced. After optimization, the incidence rate of bubble defects in the corner of QP steel has been reduced from 6.62% to 2.45%, which effectively ensures the stability of production.

关 键 词：QP钢 连铸 角部缺陷 氮气泡 氩气泡 热力学计算 

分 类 号：TF777[冶金工程—钢铁冶金]