热轧结构钢氧化铁皮结构及其对酸洗质量的影响

doi:10.13228/j.boyuan.issn0449-749x.20210552

Abstract
Figure/Table
References
Related Citation (15)

Download: PDF (3035 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract To clarify the oxide scale thickness and structure of hot rolled structural steel and the effect on pickling quality, two hot rolling processes called “High Temperature and Low Cooling Speed (HT-LCS)” and “Low Temperature and High Cooling Speed (LT-HCS)” were designed in this work. The preparation of hot rolled structural steel was carried out accordingly. Oxide scale thickness and structure in the transverse direction of hot rolled strip under different hot rolling processes and its surface morphology after pickling were analyzed by OM and SEM. On the basis of oxide scale thickness and structure difference, the pickling effects and causes of color difference defect after pickling were discussed. The results show that the oxide scale for both designed hot rolling processes is composed of outer Fe₃O₄ layer and low-temperature transformation structure of FeO located inside of oxide scale. Because of uneven distribution of temperature field during rolling process and after coiling, the thickness of oxide scale at the edge of strip is small and structure is compact, and the content of Fe₃O₄ at the edge of strip is more than that in the middle. On the other side, oxide scale is thick and porous in the middle of strip, and the transformation of FeO at low temperature is more sufficient than in the edge area. The transverse uniformity of oxide scale, including oxide scale thickness and structure distribution, was poor under HT-LCS process. Specifically, the thickness difference of oxide scale between edge and middle area of strip was 4.7 μm,and the thickness difference of Fe₃O₄ was up to 2.5 μm. However, the transverse uniformity of oxide scale was much better under LT-HCS process. The thickness difference of oxide scale between edge and middle area was 2.5 μm,which was reduced by 46.81% compared with that of HT-LCS process, and the thickness difference of Fe₃O₄ layer was 0.2 μm, which was only 8.0% of the former. The transverse uneven distribution of thickness and structure for oxide scale are the main inducement to defect of “pickled dark strip”. Eutectoid structure (α-Fe+Fe₃O₄) is loose and porous, and its pickling process is carried out in the way of “stripping”, which is more efficient in pickling. The parts of strip that are preferentially pickled will be continuously immersed in the acid solution, resulting in a large number of “erosion cracks” on the strip surface, and lead to a “color difference” finally. Optimizing the oxide scale distribution, adjusting the proportion of Fe₃O₄ and eutectoid structure in oxide scale are important to optimize production process and improve the pickling quality.

Key words： hot rolled strip hot rolling process oxide scale pickling process surface quality

Received: 09 September 2021

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	WANG En-rui
	CHEN Zi-gang
	LIU Feng-lin
	LIU Tian-wu
	ZHANG Ming

Cite this article:

WANG En-rui,CHEN Zi-gang,LIU Feng-lin等. Oxide scale structure of hot rolled structural steel and its effect on pickling quality[J]. Iron and Steel, 2022, 57(3): 71-78.

URL:

http://www.chinamet.cn/Jweb_gt/EN/10.13228/j.boyuan.issn0449-749x.20210552 OR http://www.chinamet.cn/Jweb_gt/EN/Y2022/V57/I3/71

[1] 朱阳林, 岳重祥, 李慧, 等. 汽车结构用热轧酸洗板QStE420TM的开发[J]. 金属热处理, 2018(10):50. (ZHU Yang-lin, YUE Chong-xiang, LI Hui, et al. Development of hot rolled and pickled automotive steel QStE420TM[J]. Heat Treatment of Metals, 2018(10):50.)
[2] 李文远, 郭子峰, 惠亚军, 等. 锰、铌含量对热轧酸洗QStE500TM钢板组织和性能的影响[J]. 机械工程材料, 2017, 41(12):80. (LI Wen-yuan, GUO Zi-feng, HUI Ya-jun, et al. Effects of Mn and Nb content on microstructure and properties of hot-rolled pickling steel plate QStE500TM[J]. Materials for Mechanical Enginering, 2017, 41(12):80.)
[3] 张盛攀, 焦安杰, 代玖林, 等. 轧制工艺对高强耐候钢表面氧化铁皮的影响[J]. 中国冶金, 2021, 31(7):105. (ZHANG Sheng-pan, JIAO An-jie, DAI Jiu-lin, et al. Effect of rolling process on iron oxide scale of high strength weathering resistant steel scale[J]. China Metallurgy, 2021, 31(7):105.)
[4] 李成刚, 单文超, 刘怡私, 等. 基于热轧全流程氧化铁皮控制的耐蚀性工艺[J]. 钢铁, 2021, 56(9):129. (LI Cheng-gang, SHAN Wen-chao, LIU Yi-si, et al. Corrosion resistance process based on control of oxide scale in whole process of hot rolling[J]. Iron and Steel, 2021, 56(9):129.)
[5] 于洋, 王畅, 王林, 等. 热轧板带生产中氧化的基本特点及麻点缺陷的成因与控制[J]. 轧钢, 2021, 38(5): 1. (YU Yang, WANG Chang, WANG Lin, et al. Basic characteristics of oxidation and formation mechanism and control of salt and pepper defects in hot rolled strip production[J]. Steel Rolling, 2021, 38(5): 1.)
[6] 李冠楠, 宋仁伯, 裴庆涛, 等. Cr元素对热轧耐磨钢显微组织和耐磨性的影响[J]. 中国冶金, 2021, 31(8): 35. (LI Guan-nan, SONG Ren-bo, PEI Qing-tao, et al. Effect of chromium on microstructure and wear resistance of hot-rolled wear-resistant steel[J]. China Metallurgy, 2021, 31(8):35.)
[7] 吴汉科, 贾志雷, 吕苗苗, 等. 汽车刹车片钢背用QStE420TM氧化铁皮控制技术研究[J]. 山西冶金, 2020(3):47. (WU Han-ke, JIA Zhi-lei, LÜ Miao-miao, et al. Study on QStE420TM scale control technology for steel back of automobile brake pad[J]. Shanxi Metallurgy, 2020(3):47.)
[8] 董汉君, 王银军. 影响热轧带钢氧化铁皮酸洗质量和速度的因素[J]. 机械工程材料, 2009, 33(3):83. (DONG Han-jun, WANG Yin-jun. Factors influencing pickling quality and speed of oxide scale on hot rolled strip[J]. Materials for Mechanical Engineering, 2009, 33(3):83.)
[9] 曹光明, 刘小江, 薛军安, 等. 热轧带钢氧化铁皮的酸洗行为[J]. 钢铁研究学报, 2012, 24(6):36. (CAO Guang-ming, LIU Xiao-jiang, XUE Jun-an, et al. Pickling mechanisms of hot-rolled steel strip[J]. Journal of Iron and Steel Research, 2012, 24(6):36.)
[10] 朱敏. 氧化皮的组成与结构对SS400热轧带钢耐蚀性的影响[D]. 南昌:南昌航空大学, 2011. (ZHU Min. Influence of Phase Composition and Structure of Oxide Scales on Corrosion Resistance of SS400 Hot Rolled Strip[D]. Nanchang: Nanchang Hangkong University, 2011.)
[11] 孙彬, 曹光明, 刘振宇, 等. 不同热连轧工艺参数条件下三次氧化铁皮的分析[J]. 物理测试, 2010, 28(6):1. (SUN Bin, CAO Guang-ming, LIU Zhen-yu, et al. Analysis of tertiary oxide scale with different hot rolling processes parameters[J]. Physics Examination and Testing, 2010, 28(6):1.)
[12] 邹颖. 热轧带钢氧化铁皮控制技术的研究[D]. 沈阳:东北大学, 2010. (ZOU Ying. Study on the Control Technology of Oxide Scale of Hot Rolled Strip[D]. Shenyang: Northeastern University, 2010.)
[13] Min K, Kim K, Kim S K, et al. Effects of oxide layers on surface defects during hot rolling processes[J]. Metals and Materials International, 2012, 18(2):341.
[14] Burke D P, Higginson R L. Characterization of multicomponent scales by electron back scattered diffraction(EBSD)[J].Scripta Mater, 2000, 42:277.
[15] Lucia S, Yvan H, Xavier V E, et al, High temperature deformation of oxide scale[J]. Corrosion Science, 2009, 51(2):309.
[16] 林飞, 王春峰, 李志峰, 等. 酸洗工艺对热轧酸洗板表面质量影响机理研究[J]. 轧钢, 2019, 36(2):11. (LIN Fei, WANG Chun-feng, LI Zhi-feng, et al. Study on the effect mechanism of pickling process on surface quality of hot rolled pickling plate[J]. Steel Rolling, 2019,36(2):11.)
[17] Chen R Y, Yuen W Y D. Oxide-scale structures formed on commercial hot-rolled steel strip and their formation mechanisms[J]. Oxidation of Metals, 2001, 56(1/2):89.