凝固末端電磁攪拌和輕壓下復合技術對大方坯高碳鋼偏析和中心縮孔的影響

安航航; 包燕平; 王敏; 趙立華; 王達志; 劉榮泉; 李鵬

doi:10.13374/j.issn2095-9389.2017.07.004

凝固末端電磁攪拌和輕壓下復合技術對大方坯高碳鋼偏析和中心縮孔的影響

doi: 10.13374/j.issn2095-9389.2017.07.004

1) 北京科技大學鋼鐵冶金新技術國家重點實驗室, 北京 100083
2) 北京科技大學冶金與生態工程學院, 北京 100083
3) 常熟市龍騰特種鋼有限公司, 常熟 215500

基金項目:

國家自然科學基金資助項目(51404018)

鋼鐵冶金新技術國家重點實驗室自主基金資助項目(41614014)

詳細信息

中圖分類號: TF777.2
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出版歷程
- 收稿日期: 2016-10-05

Effect of combining F-EMS and MSR on the segregation and shrinkage cavity in continuously cast high-carbon steel blooms

1) State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
2) School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
3) Changshu Longteng Special Steel Co. Ltd., Changshu 215500, China

摘要

摘要: 基于ANSYS軟件建立了310 mm×360 mm斷面大方坯連鑄過程二維凝固傳熱數學模型,并采用窄面射釘試驗及鑄坯表面測溫試驗對模型的準確性進行了驗證.通過模型研究了過熱度、拉速和二冷比水量對鑄坯中心固相率以及凝固坯殼分布的影響,并結合高碳耐磨球鋼BU的高溫拉伸試驗結果,確定了最佳的拉速以及最優輕壓下壓下區間要求.通過工業試驗對理論模型進行了驗證,并分析研究了拉速對采用凝固末端電磁攪拌(F-EMS)以及凝固末端17 mm大壓下量的輕壓下技術生產310 mm×360 mm斷面大方坯高碳耐磨球鋼BU鑄坯的偏析和中心縮孔的影響.結果表明:采用凝固末端電磁攪拌和輕壓下復合技術,通過調整拉速優先滿足輕壓下壓下區間要求,可顯著降低中心偏析、V型偏析及中心縮孔,但如果僅達到凝固末端電磁攪拌位置要求時,則鑄坯中心質量不會得到明顯改善.拉速為0.52 m·min^-1且輕壓下壓下區間鑄坯中心固相率為0.30~0.75時,偏析和中心縮孔有很大程度的改善,不合理的壓下量分配會引起鑄坯出現內裂紋以及中心負偏析.
- 大方坯 /
- 高碳耐磨球鋼 /
- 偏析 /
- 凝固末端電磁攪拌 /
- 輕壓下
Abstract: This study established a two-dimensional mathematical model of solidification and heat transfer for a bloom with a 310 mm×360 mm cross-section using ANSYS software, which was verified by nail-shooting experiments in the narrow side of the bloom and surface temperature testing. The effect of the casting process parameters, such as superheat, casting speed, and secondary cooling intensity, on the solid fraction in the strand centerline and the solidified shell was investigated. Moreover, the optimum casting speed and the optimum solid fraction in the core of the partially solidified strand throughthe soft reduction zone were determined by the model considering the hot ductility of the high-carbon wear-resistant ball steel BU. Plant trials of BU with different casting speeds were performed to validate the theoretical model and analyze the effect of the casting speed on the segregation and shrinkage cavity of BU on a 310 mm×360 mm bloom caster equipped with final electromagnetic stirring (F-EMS) combined with mechanical soft reduction (reduction amount with 17 mm). The results show that the inner defects (e. g., center segregation, V-segregation, and shrinkage cavity) significantly improve when the casting speed is adjusted to meet the required soft reduction zone as a matter of priority; otherwise, the casting speed is only adjusted to preferentially satisfy the required F-EMS stirring region. The inner quality does not show any obvious improvement. Except for the internal cracks and the negative center segregation caused by the improper distribution of the reduction amount, the inner defects (e. g., macro segregation and shrinkage cavity) significantly improve with a casting speed of 0.52 m·min^-1 and a solid fraction in the strand centerline ranging from 0.30 and 0.75 in the soft reduction zone.
- bloom /
- high-carbon wear-resistant ball steel /
- macro segregation /
- final electromagnetic stirring /
- mechanical soft reduction

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參考文獻(15)

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