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Analysis of lamellar tearing defects in the Z-directional tensile fracture of Q355 hot-rolled thick plates |
LIU Xiaofeng1, SHEN Wenjun2, ZHANG Chuangju1, PAN Shisong3, DAI Lin3, CHENG Guoguang2 |
1. Steelmaking Plant,Chongqing Iron and Steel Co., Ltd.,Chongqing 401258,China; 2. State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing, Beijing 100083,China; 3. Manufacturing Management Department,Chongqing Iron and Steel Co., Ltd.,Chongqing 401258,China |
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Abstract In order to improve the Z-directional tensile plasticity of Q355 thick plates, the reasons for the formation of Z-directional tensile defects were investigated through tensile fracture morphology observation, inclusions observation and statistics, microstructure observation and solidification structure simulation of continuous casting slab. In addition, the reasons for the appearance of MnS inclusions aggregated in the centre of the plate were further investigated. It is found that the brittle fracture platform of the tensile fracture is covered with MnS inclusions. These MnS only appear in the centre of the plate together with martensite and are accompanied by severe C and Mn segregation. The large amount of aggregated MnS in the centre of the plate create a large area of brittle fracture influence, which results in Z-directional tensile defects in the plate. The root cause of the aggregation of MnS in the centre of the plate is the overdeveloped columnar crystal of the continuous casting slab. The overdeveloped columnar crystals form a severe central segregation, which eventually leads to large aggregates of MnS and martensite together. Avoiding the appearance of overdeveloped columnar crystals and reducing the central segregation of the continuous cast slab is an effective way to improve Z-directional tensile plasticity.
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Received: 25 October 2022
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[1] |
崔风平,孙玮,彦春. 中厚板生产与质量控制[M]. 北京:冶金工业出版社,2008.
|
[2] |
曲占元,宫旭辉,薛钢. 宽厚比对船用厚板拉伸性能的影响[J]. 材料开发与应用,2014,29(3):6.
|
[3] |
冯赞,廖宏义,脱臣德,等. 炼钢连铸工艺对低合金钢特厚板Z向性能影响[J]. 金属材料与冶金工程,2021,49(5):27.
|
[4] |
孙雪娇. 低合金高强钢断后伸长率不合格原因分析[J]. 金属热处理,2020,45(5):262.
|
[5] |
马静超,张琦. 低合金中厚板延伸率不合格原因及分析[J]. 宽厚板,2020,26(5):36.
|
[6] |
李梦龙,王福明,李长荣,等. 原位观察MnS对非调质钢拉伸性能各向异性的影响[J]. 工程科学学报,2016,38(9):1257.
|
[7] |
曾光廷,李静缓,罗学厚. 非金属夹杂物与钢的韧性研究[J]. 材料科学与工程,2000(2):87.
|
[8] |
朱康峰,麻衡,宋新莉,等.550 MPa级海洋工程用钢板低温韧性波动原因分析[J].钢铁,2022,57(10):178.
|
[9] |
鲁金龙. 大规格曲轴用非调质钢中MnS形成机理及控制工艺研究[D]. 北京:北京科技大学,2020.
|
[10] |
车巨龙,鲜奋强,鲁金龙,等. 非调质钢中MnS分布对轧材横向塑性的影响[J]. 中国冶金,2020,30(6):48.
|
[11] |
黄宇,成国光,杨洪根,等. 硼铬微合金钢的脆性断裂失效分析[J]. 中国冶金,2019,29(1):38.
|
[12] |
HUANG Y, CHENG G, LI S, et al. Effect of Ti(C, N) particle on the impact toughness of B-microalloyed steel[J]. Metals, 2018, 8(11):868.
|
[13] |
全国钢标准化技术委员会.GB/T 10561—2005钢种非金属夹杂物含量的测定标准评级图显微检测方法[S].北京:中国标准出版社,1920.
|
[14] |
SPITZIG W A. Effect of sulfides and sulfide morphology on anisotropy of tensile ductility and toughness of hot-rolled C-Mn steels[J]. Metallurgical Transactions A, 1983, 14(2):471.
|
[15] |
WU M, FANG W, CHEN R M, et al. Mechanical anisotropy and local ductility in transverse tensile deformation in hot rolled steels: The role of MnS inclusions[J]. Materials Science and Engineering A, 2019, 744(28):324.
|
[16] |
汪洪峰,陶林,王勇. 高强钢连铸板坯中心偏析的分析及改善措施[J]. 连铸,2017(5):33.
|
[17] |
董鹏莉,尚海霞,王华. 铸坯及板卷典型质量缺陷成因与控制技术[J]. 中国冶金,2017,27(6):9.
|
[18] |
陶红标,张慧,范倚,等. 冷却模式对0.1%C-5%Mn钢的铸坯组织及内部裂纹的影响[J]. 钢铁,2015,50(4):53.
|
[19] |
申文君,成国光,侯雨阳. 国内外2205双相钢连铸坯凝固组织及碳偏析分析[J]. 中国冶金,2020,30(11):29.
|
[20] |
张振学,李鹏飞,赵志刚,等. GCr15轴承钢大方坯宏观碳偏析的分析[J]. 热加工工艺,2020,49(7):74.
|
[21] |
齐永顺,李丰文,玄伟东,等. 抽拉速率对DD5单晶高温合金定向凝固组织及偏析的影响[J]. 上海金属,2022,44(3):65.
|
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