|
|
Inclusion characteristics and control process optimization of 27SiMn steel |
LÜ Ming1, LIU Kunlong1, GAO Zhizhe1, SONG Baomin2, ZHANG Zhaohui1 |
1. School of Metallurgical Engineering,Xi’an University of Architecture and Technology, Xi’an 710055, Shaanxi, China; 2. Anyang Yongxing Special Steel Co., Ltd., Shagang Group, Anyang 455113, Henan, China |
|
|
Abstract High melting point inclusions in 27SiMn steel are the main cause of flaw detection defects. In order to further control the inclusions in 27SiMn steel, a study was conducted on 27SiMn steel produced by the "BOF→LF→CC" process in a domestic steel company. Liquid steel were sampled at the initial stage, before calcium treatment, after soft blowing in LF refining process, in tundish and casting billet. The samples were analyzed to investigate the characteristics of inclusions in 27SiMn steel. The results show that the inclusions are mainly MgO-Al2O3, MgO-SiO2 and Al2O3-CaO-MgO inclusions in LF refining process. In the soft-blowing and casting stage, there is existing (CaS)-Al2O3-MgO-SiO2-CaO inclusion, while a large number of CaS particles exist in the molten steel, which indicates that there are still high melting point inclusions in 27SiMn steel after calcium treatment. On this basis, the thermodynamical formation mechanism of CaS and calcium aluminate inclusions within the 27SiMn steel liquid were investigated. It is found that w([Al]) is 0.022% when w([Ca]) is controlled between 0.001 3% and 0.003 5% in liquid steel, which is conducive to the generation of 12CaO·7Al2O3. At the same time, in order to prevent the generation of CaS in molten steel and hinder the transformation of Al2O3 inclusions into 12CaO·7Al2O3, w([S]) should be controlled in the range of 0.001 5%-0.003 9%. Based on the study of inclusion characteristics and thermodynamic calculations, the process optimization scheme was proposed. The basicity of refining slag was adjusted to above 3.2 to increase the sulfur capacity, and w((Al2O3)) in slag was increased from 10%-11% to above 13% to promote the fluidity. The addition of aluminum deoxidizer was reduced from 130 kg to 120 kg. silica-calcium wire was decreased from 400 m to 200 m to carry out light calcium treatment. The industrial optimization test was conducted, and it was found that w([Ca]) in molten steel was about 0.002 4% after soft blowing, which was further reduced to about 0.0018% at the continuous casting stage, and w([S]) was controlled at about 0.002%. In the Al2O3-SiO2-CaO-(8%) MgO system, the average composition of inclusions changes from the high melting point region of 1 600-1 800 ℃ to the 1 400-1 500 ℃ in the liquid phase zone. The effect of calcium treatment is significantly improved and the quality of steel is improved.
|
Received: 31 October 2022
|
|
|
|
[1] 聂翔宇,汤海波,何蓓,等. 27SiMn钢表面激光熔覆不锈钢涂层显微组织与耐磨性研究[J]. 煤矿机械,2022,43(8):30.(NIE X Y,TANG H B,HE B,et al. Study on microstructure and wear resistance of laser cladding stainless steel coating on 27SiMn steel[J]. Coal Mine Machine,2022,43(8):30.) [2] 石淑婷,舒林森,何雅娟,等. 激光功率对27SiMn钢熔覆层组织与性能的影响[J]. 金属热处理,2022,47(5):194.(SHI S T,SHU L S,HE Y J,et al. Effect of laser power on microstructure and properties of cladding layer on 27SiMn steel[J] Heat Treatment of Metals,2022,47(5):194.) [3] 文新理,张利冲,梅珍,等. 27SiMn钢空洞型缺陷和组织的演变规律[J]. 材料热处理学报,2016,37(2):116.(WEN X L,ZHANG L C,MEI Z,et al. Evolvement rule of voids and microstructure of 27SiMn steel[J]. Journal of Material Heat Treatment,2016,37(2):116.) [4] 张娜,李智丽,董丽丽,等. 27SiMn钢圆铸坯的心部裂纹分析[J]. 热加工工艺,2022,51(19):145.(ZHANG N,LI Z L,DONG L L,et al. Analysis of cracks in core of 27SiMn steel round billet[J]. Hot Working Technology,2022,51(19):145.) [5] 季莎,张立峰,罗艳,等. 钙处理对20CrMnTiH齿轮钢中非金属夹杂物的影响[J]. 工程科学学报,2021,43(6):825.(JI S,ZHANG L F,L Y,et al. Effect of calcium treatment on nonmetallic inclusions in 20CrMnTiH gear steel[J]. Journal of Engineering Science,2021,43(6):825.) [6] 杨光,杨文,张立峰. 铝镇静钢中夹杂物钙处理改性及其影响因素[J]. 钢铁,2022,57(12):66.(YANG G, YANG W, ZHANG L F. Calcium treatment modification and influencing factorsof inclusions in aluminum-killed steel[J]. Iron and Steel,2022,57(12):66.) [7] KHURANA B,SPOONER S,RAO M B V,et al. Observation of calcium oxide treatment of inclusions in molten steel by confocal microscopy[J]. Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science,2017,48(3):1409. [8] DENG Z Y,ZHU M Y,ZHONG B J,et al. Attachment of liquid calcium aluminate inclusions on inner wall of submerged entry nozzle during continuous casting of calcium-treated steel[J]. ISIJ International,2014,54(12):2813. [9] 宋朝琦,刘威,杨树峰,等. QD08钢中Ds类夹杂物形成原因及控制[J]. 钢铁,2021,56(12):68.(SONG C Q, LIU W, YANG S F,et al. Formation reason and control of Ds inclusions in QD08 steel[J]. Iron and Steel,2021,56(12):68.) [10] 王章印,姜敏,王新华. Q345D钢精炼过程夹杂物生成及演变行为[J]. 钢铁,2022,57(2):63.(WANG Z Y,JIANG M,WANG X H. Formation and evolution of inclusions in Q345D steel during secondary refining process[J]. Iron and Steel,2022,57(2):63.) [11] 赵子荣,郝晓帅,白雪峰,等. 电弧炉短流程冶炼石油套管钢中夹杂物的演变规律[J]. 中国冶金,2022,32(8):49.(ZHAO Z R,HAO X S,BAI X F,et al. Evolution law of inclusions in petroleum casing steel during short process smelting by EAF[J]. China Metallurgy,2022,32(8):49.) [12] FAN X L,ZHANG L F,REN Y,et al. The effect of aluminum addition on the evolution of inclusions in an aluminum-killed calcium-treated steel[J]. Metals,2022,12(2). [13] 音正元,张立峰,李超,等. Q345D钢中含钙类夹杂物的演变和生成机理分析[J]. 钢铁,2020,55(11):47.(YIN Z Y,ZHANG L F,LI C,et al. Analysis of evolution and formation mechanism of calcium-containing inclusions of Q345D steel[J]. Iron and Steel,2020,55(11):47.) [14] 李成斌,刘君,蒋鹏. 车轴钢EA1 N的缺陷分析[J]. 连铸,2020(6):57.(LI C B,LIU J,JIANG P. Defect analysis of axle steel EA1 N[J]. Continuous Casting,2020(6):57.) [15] OKUMOTO K,KATO K,ONO H,et al. Thermodynamic conditions of MgO and MgO center dot Al2O3 formation and variation of inclusions formed in Fe-17 mass%cr steel at 1 873 K[J]. ISIJ International,2021,61(9):2370. [16] ZHAO W L,JIA G W,CHEN D,et al. Evolution and numerical simulation of inclusion in sub-surface layer of if steel[J]. Hot Working Technology,2015,44(9):142. [17] 王新华. 高品质冷轧薄板钢中非金属夹杂物控制技术[J]. 钢铁,2013,48(9):1.(WANG X H. Inclusion control technology for high quality cold rolled steel sheets[J]. Iron and Steel,2013,48(9):1.) [18] LI J Z,ZHENG X P. Analysis of 27SiMn hot rolled seamless steel pipe inner burr[J]. Materials Protection,2019,52(12):168. [19] 何建中,丰小冬,刘金. 液压支架用无缝钢管轧制开裂原因分析[J]. 北京科技大学学报,2012,34(1):91.(HE J Z,FENG X D,LIU J. Analysis on cracking of seamless steel tubes for hydraulic supports in the rolling process[J]. Journal of University of Science and Technology Beijing,2012,34(1):91.) [20] 边锋. 27SiMn钢坯(材)探伤缺陷分析与研究[J]. 特钢技术,2011,17(3):41.(BIAN F. Analysis and study on detected defects of 27SiMn billet(Product)[J]. Special Steel Technology,2011,17(3):41.) [21] 孙丽媛,李京社,唐海燕,等. BOF-LF-CC工艺生产27SiMn钢洁净度研究[J]. 钢铁钒钛,2010,31(3):50.(SUN L Y,LI J S,TANG H Y,et al. Research on cleanliness of 27SiMn steel produced by BOF-LF-CC process[J]. Iron Steel Vanadium Titanium,2010,31(3):50.) [22] 曾溢彬,包燕平,赵家七,等. 硅锰脱氧55SiCr弹簧钢中镁铝尖晶石的形成及演变[J]. 钢铁,2022,57(8):69.(ZENG Y B,BAO Y P,ZHAO J Q,et al. Formation and evolution of magnesia-alumina spinel in Si-Mn deoxidized 55SiCr spring steel[J]. Iron and Steel,2022,57(8):69.) [23] 孙波,张良明,吴耀光,等. 马钢SPHC钢钙处理的热力学分析[J]. 中国冶金,2017,27(1):50.(SUN B,ZHANG L M,WU Y G,et al. Thermodynamic analysis of calcium treatment of SPHC steel[J]. China Metallurgy,2017,27(1):50.) [24] 肖尊湖,刘彭,徐刚军,等. 不同钢种炉外精炼钙处理工艺的选择[J]. 钢铁,2019,54(9):62.(XIAO Z H,LIU P,XU G J,et al. Selection of calcium treatment technology of LF refining for different steel[J]. Iron and Steel,2019,54(9):62.) [25] JING G,CHENG S S,CHENG Z J. Mechanism of non-metallic inclusion formation and modification and their deformation during compact strip production (CSP) process for aluminum-killed steel[J]. ISIJ International,2013,53(12):2142. [26] XU J F,WANG K P,WANG Y,et al. Influence mechanism of silicon content in Al-killed steel on compositions of inclusions during LF refining[J]. Ironmaking and Steelmaking,2021,48(2):127. [27] LAN F J,ZHUANG C L,LI C R,et al. Effect of calcium treatment on inclusions in H08A welding rod steel[J]. Metals,2021,11(8):. [28] GUO H J, SHI C B,CHEN X C,et al. Control of MgO·Al2O3 spinel inclusions during protective gas electroslag remelting of die steel(Article)[J]. Metallurgical and Materials Transactions B:Process Metallurgy and Materials Processing Science,2013,44(2):378. [29] 蔡小锋,包燕平,林路. 钙处理过程夹杂物演变及热力学分析[J]. 工程科学学报,2016,38(1):32.(CAI X F,BAO Y P,LIN L. Evolution of inclusions during calcium treatment in liquid steel and its thermodynamic analysis[J]. Journal of Engineering Science,2016,38(1):32.) [30] 龚坚,王庆祥. 钢液钙处理的热力学分析[J]. 炼钢,2003,18(3):56.(GONG J,WANG Q X. Thermodynamic analysis of calcium treatment on liquid steel[J]. Steelmaking,2003,18(3):56.) [31] 周宇涛,杨树峰,李京社,等. 高级别船板钢生产过程中夹杂物的演变规律[J]. 钢铁,2019,54(1):33.(ZHOU Y T,YANG S F,LI J S,et al. Inclusions evolution of high-grade ship plate steel in practical production processes[J]. Iron and Steel,2019,54(1):33.) [32] GENG R M,LI J,SHI C B. Evolution of calcium aluminate inclusions by cerium treatment in al-killed steel during ruhrstahl-heraeus refining process[J]. Steel Research International,2020,91(9):32. [33] 孙彦辉,王小松,许中波,等. 高铝钢钙处理工艺热力学研究[J]. 北京科技大学学报,2011,33(增刊1):121.(SUN Y H,WANG X S,XU Z B,et al. Thermodynamics of calcium treatment on high-alumina steel[J]. Journal of University of Science and Technology Beijing,2011,33(s1):121.) [34] 蔡小锋,赵家七,张连兵,等. 铝镇静冷镦钢浇注过程中连铸机水口结瘤的原因及预防[J].上海金属,2021,43(4):77.(CAI X F, ZHAO J Q, ZHANG L B,et al. Cause and prevention of formation of blockage at continuous casternozzle during pouring aluminum-killed cold heading steel[J]. Shanghai Metals,2021,43(4):77.) [35] 韩志军,林平,刘浏,等. 20CrMnTiH1齿轮钢钙处理热力学[J].钢铁,2007,42(9):32.(HAN Z J,LIN P,LIU L,et al. Thermodynamics of calcium treatment for 20CrMnTiH1[J]. Iron and Steel,2007,42(9):32.) |
[1] |
SHEN Fengman, ZHANG Weiling, ZHENG Aijun, ZHENG Haiyan, DING Zhimin, LI Ji. Regulation of carbon deposition during preparation process of hydrogen-rich reducing gas by natural gas reforming ——An application example of H-C-O system mass balance and chemical equilibrium diagram[J]. Iron and Steel, 2023, 58(7): 9-16. |
[2] |
WANG Ju, LI Yang, JIANG Zhouhua, SUN Meng, MAO Yunqie, MA Shuai. Inclusion transformation mechanism of AISI 431 stainless steel during production[J]. Iron and Steel, 2023, 58(7): 54-63. |
[3] |
SHEN Fengman. Development of H-C-O system mass balance and chemical equilibrium diagram[J]. Iron and Steel, 2023, 58(6): 12-17. |
[4] |
WU Zhihao1,2,HE Zhu1,2,TAN Fangguan3,XIAO Aida4,LI Guangqiang1,2,WANG Qiang1,2. Development of neural networkbased prediction model of refractory lining wear behavior in LF refining process[J]. JOURNAL OF IRON AND STEEL RESEARCH , 2023, 35(6): 704-711. |
[5] |
FANG Meng-ting, YUAN Hua-zhi, XIE Xin, ZENG Jian-hua, ZHONG Hong-gang, ZHAI Qi-jie. Precipitation and growth of MnS inclusions in a heavy rail steel[J]. Iron and Steel, 2023, 58(5): 59-69. |
[6] |
HE Fei-hu, PENG Jun, ZHANG Fang, CHANG Hong-tao. Effect of Al-Ce alloy on inclusions in Al deoxidization titanium microalloyed steel[J]. Iron and Steel, 2023, 58(3): 61-72. |
|
|
|
|