|
|
|
| Optimization research on downgrade strategy of transition slabs of thin size and high quality automobile sheet |
| ZHANG Tao, WANG Xinhua, WU Zhongyou, LI Jinbo, GAO Fubin, LIU Junshan |
| Hansteel Co., Ltd., HBIS Group, Handan 056015, Hebei, China |
|
|
|
|
Abstract Many automobile enterprises recently decreased the thickness of the steel sheet to about 0.65 mm,which resulted in a remarkable increase of cracking defects when large deformation is applied,particularly on the steel sheets produced from the transition slabs in continuous casting. The cracking of the thin gauge automobile sheets were investigated by the high-magnification observation,and composition analysis of the cracking were carried out by scanning electron microscopy and energy spectrum analysis. The flow and mixing characteristics of the molten steel in succeeding heat entered the tundish were analyzed by numerical simulation,and the results find out that the cracking was caused mainly inclusions of Al2O3 and calcium aluminates. More cracking occurred on steel sheets made from the transition slabs mainly due to a small amount of liquid steel being oxidized and a few tundish slag drops involved in the liquid steel at the time when the succeeding heat starts casting. The prediction model of the transient slab length was developed,and the applicability of the mathematical model was verified by sampling and analyzing the mixed-casting slabs. The cracking occurred mainly on sheets of the slabs cast within the time when the mass percent of the steel of the succeeding heat reached 20%-80% at the exit of the tundish. The tundish with the flow control structure of double weirs and double dams has the shortest time to produce the transition slabs and the time is 7.33 min. Industrial experiments were carried out based on the research results,and the actual production data of 30 casting sequences were tracked. According to the previous downgrade strategy of transition slabs,84 slabs needed to be downgraded,but through optimization,only 38 transition slabs should be downgraded. The amount of degradation was reduced from 41.38% to 18.72%,while the stamping cracking rate did not increase,and remained the advanced control level at less than 0.025%.
|
|
Received: 26 April 2023
|
|
|
|
[1] MELVILLE S D,BRINKMEYER L. Evaluating steelmaking and casting practices which affect quality[C]//78th Steelmaking Conference Proceedings. Nashville:[s.n.],1995:563.
[2] EMI T. Steelmaking technology for the last 100 years:Toward highly efficient mass production systems for high quality steels[J]. ISIJ International,2015,55(1):36.
[3] 刘喜锚. 控流装置对四流中间包钢水洁净度的影响[J]. 连铸,2022(5):88. (LIU X M. Effect of flow control device on steel cleanliness in four-flow tundish[J]. Continuous Casting,2022(5):88.)
[4] 隋亚飞,陈杰,刘彭,等. 连铸混浇坯成分变化规律及模型的研究[J]. 连铸,2019(4):62. (SUI Y F,CHEN J,LIU P,et al. Research and model prediction on composition change of continuous casting intermixing slab[J]. Continuous Casting,2019(4):62.)
[5] HUANG X,THOMAS B G. Modeling of steel grade transition in continuous slab casting processes[J]. Metallurgical and Materials Transactions B,1993,24(2):379.
[6] 钟巍,徐蕊,王海军,等. 换包过程中连铸中间包内多相流动行为研究[J]. 炼钢,2022,38(4):63.(ZHONG W,XU R,WANG H J,et al. Multiphase flow behavior in a continuous casting tundish during ladle change[J]. Steelmaking,2022,38(4):63.)
[7] 朱坦华,周秋月,任英,等. 二次氧化过程IF钢中间包中夹杂物演变行为[J]. 钢铁,2020,55(3):35.(ZHU T H,ZHOU Q Y,REN Y,et al. Inclusion evolution in IF steel during tundish reoxidation[J]. Iron and Steel,2020,55(3):35.)
[8] 李杰. 连铸异钢种混浇坯控制模型的开发与应用[J]. 冶金与材料,2019,39(3):44. (LI J. Development and application of a control model for continuous casting of different steel grades and mixed slabs[J]. Metallurgy Materials,2019,39(3):44.)
[9] 王汝栋,苏旺,崔衡,等. 基于F曲线的中间包流场优化[J]. 工程科学学报,2020,42(增刊1):95. (WANG R D,SU W,CUI H,et al. Optimization of the tundish flow field based on F-curve[J]. Chinese Journal of Engineering,2020,42(s1):95.)
[10] 陆云威,崔素兰. 连铸混浇坯的过度时间及影响因素[J]. 炼钢,1995(4):30.(LU Y W,CUI S L. The transition duration and the influential factors of compound casting billets[J]. Steelmaking,1995,11(4):30.)
[11] 毕经汉,唐萍,文光华,等. 异钢种连浇交接坯长度与位置预测模型[J]. 过程工程学报,2012,12(2):271.(BI J H,TANG P,WENG G H,et al. Prediction model of intermixing slab length and location in continuous grade transition casting process[J]. Chinese Journal of Process Engineering,2012,12(2):271.)
[12] 张剑君,彭著刚,王春锋,等. 薄板坯单流中间包混浇水力学模型试验研究[J]. 炼钢,2017,33(4):19.(ZHANG J J,PENG Z G,WANG C F,et al. Research on continuous casting grades transition process by hydraulic model of CSP 45t single strand tundish[J]. Steelmaking,2017,33(4):19.)
[13] 李玉刚,董金刚,李刚,等. 异钢种连浇过程中的交接部铸坯预测模型[J]. 重庆大学学报(自然科学版),2006,29(8):119.(LI Y G,DONG J G,LI G,et al. Prediction model of intermixing slab length during continuous casting grade transition process[J].Journal of Chongqing University(Natural Science),2006,29(8):119.)
[14] 郭春牧,于帆,张欣欣. 异钢种连浇过程中钢液流动与混合的数值模拟[J]. 中国冶金,2006,16(1):35.(GUO C M,YU F,ZHANG X X. Numerical simulation of steel flow and mixing during grade transition casting[J]. China Metallurgy,2006,16(1):35.)
[15] 李彩霞. 连铸异钢种混浇成分变化规律的研究[J]. 宽厚板,2017,23(3):12.(LI C X. Study on composition variation law of steel grade transition during continuous casting[J]. Wide and Heavy Plate,2017,23(3):12.)
[16] MAZUMDAR D. Review,analysis,and modeling of continuous casting tundish systems[J]. Steel Research International,2019,90(4):1800279.
[17] SIDDIQUI M I H,KIM M H. Optimization of flow control devices to minimize the grade mixing in steelmaking tundish[J]. Journal of Mechanical Science and Technology,2018,32(7):3213.
[18] AHN J H,YOON J K,LEE J E. Analysis of mixed grade transition in continuous thin slab casting with EMBR[J]. Metals and Materials International,2002,8(3):271.
[19] CWUDZIN＇SKI A. Physical and mathematical simulation of liquid steel mixing zone in one strand continuous casting tundish[J]. International Journal of Cast Metals Research,2017,30(1):50.
[20] 李涛,常立忠,从俊强,等. 异钢种连浇工艺参数对交接坯长度的影响[J]. 连铸,2016,41(2):13. (LI T,CHANG L Z,CONG J Q,et al. Influence of different steel grade continuous casting process parameters on the transfer slab length[J]. Continuous Casting,2016,41(2):13.)
[21] 孙增晓,赵增武,金永丽. 异钢种连浇过程的水模研究[J]. 内蒙古科技大学学报,2010,29(3):210. (SUN Z X,ZHAO Z W,JI Y L. Water modeling experiment on continuous casting grade transition process[J]. Journal of Inner Mongolia University of Science and Technology,2010,29(3):210.)
[22] 李雨倩,陈超,成国光,等. 中间包水模型数据的流出百分比分析方法[J]. 过程工程学报,2022,22(11):1447.(LI Y Q,CHEN C,CHENG G G,et al. Analysis method for outflow percentage of water model data of tundishes[J]. Chinese Journal of Process Engineering,2022,22(11):1447.)
[23] CHO M J,KIM S J. A practical model for predicting intermixed zone during grade transition[J]. ISIJ International,2010,50(8):1175.
[24] ALIZADEH M,EDRIS H,PISHEVAR A R. Behavior of mixed grade during the grade transition for different conditions in the slab continuous casting[J]. ISIJ International,2008,48(1):28.
[25] HUANG X,THOMAS B G. Intermixing model of continuous casting during a grade transition[J]. Metallurgical Transactions B,1996,27(4):617.
[26] 郑淑国,朱苗勇. 多流连铸中间包各流流动特性一致性的判别[J]. 过程工程学报,2006,6(4):522.(ZHENG S G,ZHU M Y. Criteria on the similarity of melt flow among strands in multi-strand continuous casting tundish[J]. Chinese Journal of Process Engineering,2006,6(4):5222.)
[27] 安航航,焦树强,孙彦辉,等. 板坯连铸异钢种连浇混浇坯长度及成分变化模型的开发及应用[J]. 工程科学学报,2021,43(12):1656. (AN H H,JIAO S Q,SUN Y H,et al. Development and application of intermixed length and composition variation model in continuous slab casting processes during a grade transition[J]. Chinese Journal of Engineering,2021,43(12):1656.)
[28] 邓小旋,王新华,李林平,等. 交换钢包过程对IF钢连铸板坯表层洁净度的影响[J]. 北京科技大学学报,2014,36(7):880.(DENG X X,WANG X H,LI L P,et al. Effect of ladle change process on the surface cleanliness of IF steel continuous casting slabs[J]. Chinese Journal of Engineering,2014,36(7):880.)
[29] 内堀秀男. 高品质洁净钢的现状及将来[C]//第126·127回西山記念技術講座论文集. 大阪:日本钢铁协会,1988:1.(HIDEYO N. The current situation and future of high quality clean steel[C]//The 126-127th Xishan Memorial Technology Lecture Proceedings. Osaka:Japan Steel Association,1988:1.)
[30] 丸川雄净. 大量生産规模における不純物元素の精錬限界[M]. 东京:日本钢铁协会,1996.(MARUKAWA Y. Refining Limits of Impurity Elements in Mass Production[M]. Tokyo:The Iron and Steel Institute of Japan,1996.)
[31] SAHAI Y,EMI T. Tundish Technology for Clean Steel Production[M]. New Jersey:World Scientific,2008. |
| [1] |
LÜ Ming, LIU Kunlong, GAO Zhizhe, SONG Baomin, ZHANG Zhaohui. Inclusion characteristics and control process optimization of 27SiMn steel[J]. Iron and Steel, 2023, 58(6): 61-71. |
| [2] |
JIAO Ao-teng, YANG Shu-feng, LI Jing-she, SONG Jing-ling, LI Heng-hua, ZHANG Fu-jun. Evolution of inclusions in 26CrMo7S steel produced by EAF-LF-VD-CC process[J]. CONTINUOUS CASTING, 2023, 42(2): 28-33. |
| [3] |
SONG Bao-min, SHI Shu-guang, LIU Kun-long, LÜ Ming. Formation and evolution of nonmetallic inclusions in 27SiMn steel[J]. CONTINUOUS CASTING, 2023, 42(2): 57-62. |
| [4] |
LIANG Yin, ZHU Hangyu, LUO Lingen, LIU Zhi, WANG Bao. Image recognition of non-metallic inclusions based on deep learning[J]. Iron and Steel, 2023, 58(12): 62-70. |
| [5] |
ZENG Li, LUO Yanzhao, LIU Yanqiang, ZHAO Changliang, JI Chenxi, XU Haiwei. Control technology and source of large-size calcium aluminate inclusions in automobile sheets[J]. Iron and Steel, 2023, 58(10): 67-74. |
| [6] |
Lei Cao, Li-guang Zhu, Zhi-hong Guo. Research status of inclusions in bearing steel and discussion on non-alloy deoxidation process[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2023, 30(1): 1-20. |
|
|
|
|
2023, Vol. 58 
