HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015Engineering Steels 2015 CONFERENCE PROCEEDINGS
Held November 11-13th, 2015 Hangzhou, Zhejiang Province, China
Organized by:
Chinese Academy of Engineering (CAE)
Supported by:
The Vanadium International Technical Committee (Vanitec)
HSLA Steels 2015, Microalloying 2015 & Offshore
Engineering Steels 2015 CONFERENCE PROCEEDINGS
JWBT1725-TMS.indd iv 30 August 2015 9:54 AM
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ISBN 978-1-119-22330-6
10 9 8 7 6 5 4 3 2 1
Niobium Solar Mobile Project – High Strength Niobium Microalloyed Steel as a Solution to Improve Electric Super Scooter and Motorcycle Performance .....................................................41
Terry Richards, Erik Kauppi, Lauren Flanagan, Eduardo A.A.G. Ribeio, Marcos A. Stuart Nogueira, and Ian McCourtney
Evolution of Microalloyed Steels Since Microalloying ’75 with Specific Emphasis on Linepipe and Plate .............................................................................................................................53
J. Malcolm Gray and F. Barbaro
Modern Niobium Microalloyed Steels for the Automotive Industry ......................................................................71 Debanshu Bhattacharya
Design of Reforma 509 with High Strength Steel ..................................................................................................85 Stuart Smith, William Whitby, and Marc Easton
Microalloyed Engineering Steels with Improved Performance ..............................................................................97 Wolfgang Bleck, Margarita Bambach, and Vera Wirths
Technical Requirements for the Development of Marine Steel in China .............................................................121 Hang SU, Tao PAN, Feng CHAI, and Caifu YANG
Physical Metallurgy
Effect of Nitrogen on Transformation Behaviors and Microstructure of V-N Microalloyed Steel .......................135 Zhao Baochun, Zhao Tan, Li Guiyan, and Lu Qiang
Quantifying the Effect of Nb and Mo on Transformation Products Using Advanced EBSD Analysis ................143 Jennifer M. Reichert and Matthias Militzer
Decomposition of Supercooled Austenite in Continuous Cooling Transformation Process of a Mn-Mo-Ni Low Alloy Steel .............................................................................................................151
C.W. Li, L.Z. Han, Q.D. Liu, X.G. Tao, J.F. Gu, and W.M. Zhang
Effect of High Magnetic Field on the Pearlite Transformation of Hypoeutectoid Steel .......................................159 Li Jing and Zhang Guohong
vivi
Pan Tao, Yang Caifu, and Su Hang
Thermodynamic Calculations and Precipitation Simulations of HSLA Steels ....................................................173 Shan Jin, Qing Chen, and Johan Bratberg
Determination of Dynamic Recrystallization Process by Equivalent Strain ........................................................179 Xiaomei Qin and Wei Deng
High-Strength Low-Alloy Steel Strengthened by Multiply Nanoscale Microstructures ......................................187 Y.F. Shen and L. Zuo
Grain Refinement and Toughening of Low Carbon Low Alloy Martensitic Steel with Yield Strength 900 MPa Grade by Ausforming ....................................................................................................195
Zhaodong Li, Xinjun Sun, Zhigang Yang, and Qilong Yong
Effect of Mo Addition on the Precipitation Behavior of Carbide in Nb-Bearing HSLA Steel .............................203 Zhengyan Zhang, Qilong Yong, Xinjun Sun, Zhaodong Li, Zhengqiang Wang, Shitong Zhou, and Guodong Wang
Application of Nano-Scale Precipitate Engineering of TiN-NbC Composite in 32mm K60-E2 Grade Plate Rolling ...............................................................................................................................................211
S.V. Subramanian, Ma Xiaoping, Nie Wenjin and Zhang Xiaobing
Precipitation Behavior of Nanometer-Sized Carbides in a Nb-Ti-Bearing Low-Carbon Steel ............................223 Li Xiaolin, Wang Zhaodong, Deng Xiangtao, Yang Yong, Song Dan, and Wang Guodong
Measurement Uncertainty of Mechanical Property in Tensile Tests: Strain Rate Embrittlement of HSLA Steels ..........................................................................................................................................................229
Tingdong Xu, Chong Shao and Kai Wang
in Nb Added High Strength Dual Phase Steels .....................................................................................................237 O. Girina, N. Fonstein, O. Yakubovsky, D. Panahi, D. Bhattacharya, and S. Jansto
The Influence of Carbon Content and Cooling Rate on the Toughness of Mn-Mo-Ni Low-Alloy Steels............247 Huibin Liu and Hanqian Zhang
Comparative Analysis of Precipitation Effects in Microalloyed Austenite and Ferrite Under Hot and Cold Forming Conditions .....................................................................................................................................253
Krzysztof Muszka, Marcin Kwiecien, Janusz Majta, and Eric J. Palmiere
Niobium-Based Alloy Design for Structural Applications: Processing-Structure-Property Paradigm .................261 Devesh Misra
Influence of Micro-Texture on Delamination of Hot-Rolled High Strength Low Alloyed Steel Sheets ..............267 Sungil Kim, Shi-Hoon Choi, Sung-Hwan Kim, Seok-Jong Seo and In-Shik Suh
Effect of Initial Microstructure on the Mechanical Properties of an Intercritically Quenched and Tempered HB400 Grade Heavy Plate ............................................................................................................273
Zhen Fan, Qu Jinbo, Zhang Kuan, and Qiao Kun
Thermomechanical Processing of Structural Steels with Dilute Niobium Additions ...........................................281 Z. Cui, J. Patel, and E.J. Palmiere
Application of In-Situ Material Characterization Methods to Describe Role of Mo During Processing of V-Bearing Micro-Alloyed Steels ......................................................................................................................289
Vit Janik, Sam Clark, Prakash Srirangam, Arjan Rijkenberg, and Sridhar Seetharaman
The Influence of Mo, Cr and B Alloying on Phase Transformation and Mechanical Properties
viivii
Xu Luo, Yong-Lin Kang, Cai-Shui Yang, and Jun-Hong Li
Process Metallurgy
Through-Thickness Homogenization in Thin Slab Direct Rolling of Nb Microalloyed Steels ............................309 B. Pereda, P. Uranga, B. López, J.M. Rodriguez-Ibabe, D. Stalheim, R. Barbosa, and M.A. Rebellato
Study on the Control of Cleanliness for X90 Pipeline in the Secondary Refining Process ..................................317 Ren Sheng Chu, Jin Gang Liu, and Zhan Jun Li
Hot Strength during Coiling of Low C and Nb-Microalloyed Steels ...................................................................323 R. Maubane, K.M. Banks, and A.S. Tuling.
Research of Helical Magnetic Field Stirrer in Bloom Continuous Casting ..........................................................329 Guo Qing-Tao, Liao Xiang-Wei, Jia Ji-Xiang, Huang Yu-Ping, Tang Xue-Feng, and Zou Huan
Modelling Microstructure Evolution during Hot Rolling of HSLA Steels in a Steckel Mill ...............................335 W. Almeida, H. Rodrigues, M. Rebellato, F. Bastos, and R. Barbosa
The Influence of Vanadium Microalloying on the Production of Thin Slab Casting and Direct Rolled Steel Strip .......................................................................................................................................343
Yu Li and David Milbourn
Reference Yield Strength Calculated by Rolling Force Model .............................................................................351 LU Shiping and LI Jiading
Metallurgical Understanding to Extend Cold Rolled HSLA to Higher Strength Levels ......................................357 C. Philippot, C. Föjer, and L. Duprez
Effect of Cooling Rate on Microstructure and Centerline Segregation of a High-Strength Steel for Shipbuilding ....................................................................................................................................................365
Qibin Ye, Zhenyu Liu, and Guodong Wang
Influence of Finish Rolling Temperature on Microstructure and Property of Non-Quenched and Tempered Steel ......................................................................................................................................................371
Yakun Gao, Yinli Chen, Liming Xu, and Yuhao Wang
Strengthening Mechanisms of V-Ti-Mo Microalloyed 900 Mpa Hot-Rolled Ferritic Steel .................................379 Ke Zhang, Zhaodong Li, Xiaochen Han, Xinjun Sun, and Qilong Yong
Development of Processing Maps for Intercritical Annealing Using the Phase Field Approach .........................387 Benqiang Zhu and Matthias Militzer
Optimization of Heat Treatment Process of High Strength WDL690D Steel ......................................................395 Wang Zhiwu, Ju Guangyu, Hu Ningyin, and Gong Xueting
Effects of Heat Treatment Process on Microstructure and Mechanical Properties for Extra-Thick High-Strength Steel Plate ......................................................................................................................................403
Xuesong Wang, Yang Zou, Yuefei Zhang, Xuefeng Zhang, XinSong, Zhiyong Wang, Zhanbin Dong, Yongli Liu, and Xuejun Bai
Influence of Non-Uniform Water Cooling on the Shape of Rolled H-Shaped Beam ...........................................411 Jung, Seung Hoon, Yun, Myung Seok, Koo, Bon Seung, Lee, and Kwang Keun
Contributions of Vanadium to Properties of Heat Treated Medium Carbon Forging Steels .................................419 L.M. Rothleutner, C.J. Van Tyne, R.J. Glodowski, J.G. Speer, and D.K. Matlock
viiiviii
A New Method to Compute the Behavior of Phase Transformations and Depth of the Decarburized Ferrite Layer, Scale Thickness of Steel from Measured Temperatures ....................................427
Sangwoo Choi, Il-Heon Son, Joong-Ki Hwang, Young Soo Chun, Nam-Suk Lim, Hyun-Ho kim and Jang-Yong Yoo
Partial-Isothermally-Treated Low Alloy Ultrahigh Strength Steel with Martensitic/Bainitic Microstructure .....433 Quanshun Luo, Matthew Kitchen, Vinay Patel, Martin Filleul, and Dave Owens
Welding Niobium Bearing HSLA Steels ‘Myths and Magic’ ..............................................................................439 Dr Phil Kirkwood
Effects of the Performance of Ship Steel for High Heat Input Welding by Micro-Alloy Element ......................447 Kuijun Fu, Fengya Hu, Jiaji Wang, Fangfang Liu, Yumei Ji, and Jianbo Jiang
Weld HAZ Properties in Modern High Strength Niobium Pipeline Steels...........................................................453 Frank Barbaro, Zhixiong Zhu, Lenka Kuzmikova, Huijun Li, and Han Jian
Development of 690MPa High Strength Steel with Low Yield Ratio and Good Weldability for Building Structures in Wisco ...........................................................................................................................459
Mingwei Tong, Zexi Yuan, Kaiguang Zhang, and Wei Fan
Effect of Pipe Body Alloy on Weldability of X80 Steel .......................................................................................467 Xianglei Kong, Guojian Huang, Kuijun Fu, Fangfang Liu, Minghao Huang, and Yinghui Zhang
The Development and Microstructure Analysis of High Strength Steel Plate NVE36 for Large Heat Input Welding ........................................................................................................................................................475
Zhang Peng, Xie Liangfa, Wei Ming, and Li Jianli
Characterization of the Multi-Pass Weld Metal and the Effect of Post-Weld Heat Treatment on Its Microstructure and Toughness ....................................................................................................................481
Xuelin Wang, Chengjia Shang, and Xuemin Wang
Effect of Heat-Affected Zone on Spot Weldability in Automotive Ultra High Strength Steel Sheet ...................489 Akihiko Nagasaka, Junya Naito, Shota Chinzei, Tomohiko Hojo, Katsumi Horiguchi, Yuki Shimizu, Takuro Furusawa and Yu Kitahara
Analysis of AOD Converter Trunnion Rupture and the Welding Repair Process .................................................495 Junwei Wang, Hongliang Li, and Yanli Ma
Development of High Heat Input Welding Offshore Steel as Normalized Condition ..........................................503 Wei Deng and Xiaomei Qin
Research on Wheel Steel Welding Cracks Caused by Quenching Stress .............................................................509 Li Guan-Nan
Microstructures and Continuous Cooling Transformation of CGHAZ in E36 Class V-N-Ti, V-Ti and Nb-Ti Shipbuilding Steels .....................................................................................................................................517
Zhongran Shi, Ruizhen Wang, Qingfeng Wang, Hang Su, Feng Chai, and Caifu Yang
Study on Continuous Cooling Transformation Behavior of Coarse Grain Heat-Affected Zone in V-N-Ti and Nb-V-Ti Microalloyed Offshore Platform Steels ...............................................................................525
Feng Lu, Feng Chai, Guangping Cheng, Hang Su, Nan Li, and Caifu Yang
automotive steels
Effect of Nb on Delayed Fracture Resistance of Ultra-High Strength Martensitic Steels ....................................541 Rongjie Song, Nina Fonstein, Narayan Pottore, Hyun Jo Jun, Debanshu Bhattacharya, and Steve Jansto
ixix
Development and Application of the High-Strength Wear-Resistance Steel Used for the Lightweight Heavy-Duty Dump Mining Truck ..............................................................................................549
Linhao Gu, Zhenqiang Wang, Yongqing Zhang, Aimin Guo, and Doug Stalheim
Optimization of High Performance Special Steels ...............................................................................................557 Hardy Mohrbacher
Research on the Microstructures and Mechanical Properties of Ti Micro-Alloyed Cold Rolled Hot-Dip Galvanizing DP980 Steel ......................................................................565
Yun han, Shuang Kuang, Xiumei Qi, Chunqian Xie, and Guanghui Liu
Development of Press Hardening Steel with High Resistance to Hydrogen Embrittlement ................................571 Jian Bian, Hardy Mohrbacher, Hongzhou Lu and Wenjun Wang
Effect of Annealing Temperature on Microstructure and Mechanical Properties of Hot-Dip Galvanizing DP600 Steel ......................................................................................................................................577
Sun Hai-yan, Liu Zhi-li, Xu Yang, Shi Jian-Qiang, and Wang Lian-xuan
Research on Forming Mechanisms and Controlling Measurements for Surface Light Spot Defects of Galvanizing Steel Coils for Automobile Use .................................................583
Wei Guangmin, Sun Haiyan, Shi Jianqiang, Wang Lianxuan, and Wu Haihong
The Influence of Niobium on the Microstructure and Properties of CrMo Steel .................................................589 Xiangru Chen, Ming You, Ai’min Guo, Wei Zhang, Haicheng Li, Yang Xu, and Qijie Zhai
The Development of Lightweight Commercial Vehicle Wheels Using Microalloying Steel ...............................597 Hongzhou Lu, Lilong Zhang, Jiegong Wang, Zhaozhi Xuan, Xiandong Liu, Aimin Guo, Wenjun Wang, and Guimin Lu
The Effect of Niobium Microalloying on Processing and Application Properties of Dual Phase Steel ...............605 Hardy Mohrbacher
A Low Cost Ferritic Stainless Steel Microalloyed by Higher Nb for Automotive Exhaust System.....................613 Erhu Chen, Xuelin Wang, and Chengjia Shang
Improving Strength-Ductility Balance of High Strength Dual-Phase Steels by Addition of Vanadium ..............621 Yu Gong, M. Hua, J. Uusitalo and A.J. Deardo
The Mechanical Property of Batch Annealed High Strength Low Alloy Steel HC260LA ...................................635 Xiaojiang Yang, Mingsheng Xia, Hongbo Zhang, Bin Han, and Guilan Li
Study on the Effect of Secondary Banded Structure on the Fatigue Property of Non-Quenched and Tempered Micro Alloyed Steel .............................................................................................641
Cheng Yajie, Liao Qingliang, and Zhang Yue
Research of 600C Grade Welding V-N Micro-Alloyed Steel Used on Truck Axle Housing After Thermal Forming ..................................................................................................................................................649
Wang Quanli, Pan Hui, and Liu Qingmei
Product Design and Production Practice of 700MPa High Strength Hot Rolled Strip for Auto Axle Tube .....................................................................................................................................................655
Pan Hui, Wang Zhao-Dong, Hui Ya-Jun, Cui Yang, Deng Xiang-Tao, and Bao Chun-Lin
Effect of Cerium on Behavior of High Temperature Deformation of IF Steel .....................................................663 Gao Fu-bin, Fan Jia, and Li Jian-Wen
Research and Process-Optimization on Mixed Crystal Caused Uneven-Performance of High-strength Structural Car Steel QStE500TM ..................................................................................................669
Li Jian-Wen and Liu Hong-yan
Development of Low Carbon Niobium Bearing High Strength F-B Dual Phase Steel with High Hole Expansion Property ......................................................................................................................................677
Lin Zhang, Ming-sheng Xia, Zi-liu Xiong, Yan-bing Du, Zhi-ming Qiao, and Hong-bo Zhang
xx
Research and Development of Heavy Gauge X80 Pipeline Plate Utilizing Optimized Rolling and Cooling Process ....................................................................................................................................................693
Shaopo Li, Jiading Li, Wenhua Ding, and Hai Zhang
Controlled Technology of DWTT Property of Heavy Gauge X80 Strip ..............................................................699 Shujun Jia, Yongqing Zhang, Tao Niu, Aimin Guo, and Qingyou Liu
An Investigation of Aging Behaviour in Microalloyed Steel (X70) UOE Pipe ....................................................707 J.B. Wiskel, J. Ma, D.G. Ivey, and H. Henein
Effect of Vanadium Addition on API X100 Linepipe Steel ..................................................................................715 S. Nafisi, M. Arafin, B.S. Amirkhiz, R. Glodowski, L. Collins, and J. Szpunar
Latest Development and Application of High Strength and Heavy Gauge Pipeline Steel in China .....................721 Zhang Yongqing, Guo Aimin, Shang Chengjia, Liu Qingyou, J. Malcolm Gray, and Frank Barbaro
Effect of Deformation in Roughing Mill on Mechanical Properties of Microalloyed API Steel Grades .............727 Milind Patil, Bharat Arikere, Amitabh Sarna, and Marwan Al-Mojil
Precipitation and Dislocation Strengthening Behaviour of Grade X80 Steel for Pipeline with Strain Based Design ..............................................................................................................................................733
Weihua Sun, Shu-e Hu, Guobao Li, and Hao Yu
Research and Development of Nb-Bearing Steels for Low Temperature Service Pressure Vessels .....................743 Zhongzhu Liu and Aimin Guo
Research on Manufacture and Quality Control of Medium Carbon Vessels for Resistance to Hydrogen Induced Cracking .................................................................................................................................751
ZhaoXinyu, Zou Yang, Liu Yang, Zhao Nan, Fan Yanqiu, Qin Liye, and LvYanchun
Investigation and Application of Nb Microalloying Technology in Seamless Steel Tube with High Performance ..........................................................................................................................................................759
Chuanyou Zhang Qian Wang, Yu Sun, Huibin, Wang, Wei Zhang, Qingfeng Wang, Aimin Guo, and Kaiming Sun
Development of Cr-Mo Steel Plate for Gasifier in Wuyang .................................................................................767 Yanyang Wu, Ming Wei, Liangfa Xie, Sheng Liu, and Jincheng Yuan
Effect of Austenite Deformation and Continuous Cooling on Microstructure Evolution in a Pipeline Steel ..................................................................................................................................................775
H. Zhao, JM Gray and EJ Palmiere
Microstructure Development during Roughing and Intermediate Cooling of Thick HTP Linepipe Steels ...................................................................................................................................783
Kevin Banks and Rorisang Maubane
Deformation Characteristic of 617B Nickel Base Superalloy for 700C Ultra-Supercritical Boilers ...................791 Yan Wang, Fang-hong Xu, Yang Li, Li Zeng, Sha Li, and Jian-Min Li
Nb-Ti-Mo Ferrite Matrix Micro-Alloy Steel with Nanometersized Precipitates for Refuge Alternative Plate ..................................................................................................................................799
CaoJianming, WuHuibin, ZhangPengcheng, CaiQingwu, and Tang Di
The Stress Corrosion Performance Research of Three Kinds of Commonly Used Pipe Materials ..............................................................................................................................................807
Yayun Hu, Yiliang Zhang, and Xiaoliang Jia
xixi
Graphitisation: A Potential New Route to Free-Machining Steels .......................................................................817 Aqil Inam, Kejian He, and David Edmonds
Development and Application of High Strength TMCP Plate for Coal Mining Machinery .................................823 Zhang Yongqing, Guo Aimin, and Yao Liandeng
Austenite Continuous Cooling Transformation of Wear-Resistant Steel with Hardness 500HBW .....................829 Feng Yong, Liu Xiaodong, and Sun Demin
Phase Transformation during Continuous Cooling of NM550 Wear-Resistant Steel ...........................................835 Xin Zhang, Renbo Song, Wenming Xiong Erding Wen, Zhonghong Wang, and Ke Guo
Effect of Epsilon Carbides on Mechanical Properties and Wear Resistance of Low Alloy Abrasion Resistance Steel .....................................................................................................................................843
Xiangtao Deng, Tianlian Fu, Junhui Li, Xiaolin Li, Zhaodong Wang, and Guodong Wang
Industrial Test of High Strength Steel Plates Free Boron Q890D Used for Engineering Machinery ...................851 Ruifeng Dong, Zetian Liu, and Jun Gao
Design of High Manganese Steels: Calculation of SFE and Ms Temperature .....................................................857 Dinesh Kumar
Effect of Soluble Al Content on the Microstructure and Property of Batch Annealed Ti-IF Steels .....................865 Mingsheng Xia, Ge Jie, Bin Han, Guilan Li, Shichuan Yu, and Hongbo Zhang
Hot Deformation Behavior of NM550 Wear-Resistant Steel ................................................................................873 Erding Wen, Renbo Song, Wenming Xiong, Xin Zhang, Zhonghong Wang, Ke Guo, and Jingfan Hu
Benefits of High Strength Microalloyed Rebar ....................................................................................................881 Michael Wright
Nb Microalloyed Modern Ferritic Stainless Steel ................................................................................................887 Zhang Wei, Mariana Oliveira, Jiang Laizhu, Fan Guangwei, and Fu Junyan
Application Research of Nb Microalloying on Medium and High Carbon Long Products .................................903 Zhang Yongqing, Guo Aimin, Wang Quanli, Zhang Xiaobing, Nie Wenjin, and Steven G. Jansto
Effect of Vanadium on the Microstructure and Elevated Temperature Properties of Fire Resistant Steels ..............................................................................................................................................909
Liu Qingchun, Yong Qilong, and Zheng Zhiwang
R&D and Applications of V-N Microalloyed Steels in China ..............................................................................917 Yang Caifu
Use of Niobium High Strength Steels with 450 MPA Yield Strength for Construction .......................................931 Leonardo Silvestre, Peter Langenberg, Thiago Amaral, Marcelo Carboni, Marcos Meira, and Alexandre Jordão
Effect of Nitrogen on the Vanadium Precipitation Behavior of Higher Yield Strength Weathering Steels ..................................................................................................................................................941
Liu Qingchun, Yong Qilong, and Zheng Zhiwang
Microstructure and Mechanical Properties of Nb Microalloyed Q370qE-HPS Bridge Steel Produced by TMCP ..........................................................................................................................947
Xi Tian, Qingfeng Wang, Hongyan Sun, Ming Li, Zhibin Fu, Jun Hong, Houxin Wang, and Aimin Guo
xiixii
Xiaoshu Wang, Zhijun Zhang, and Peng Zhang
Composition Optimization and Mechanical Properties Control for 500MPa High Strength Ribbed Bars ...........................................................................................................................................................967
Xiang Youbing, Lan Lan, Zhang Chaofa, Liu Shanxi, and Wang Qiang
Sulfur Content Precision Control Technology for CO2-Shielded Welding Wire Steel .........................................973 Zhang Chaofa, Hao Huaqiang, Xiang Youbing, and Liu Shanxi
Metallurgical Mechanism and Niobium Effects on Improved Mechanical Properties in High Carbon Steels ........................................................................................................................................................981
Steven G. Jansto
Douglas G. Stalheim, Fu Peimao, Gu Linhao, and Zhang Yongqing
Nb Effects on the Dynamic Recrystyllization Behavior and Mechanical Properties of V/Ti Alloyed Non-Quenching and Tempering Steel .......................................................................................1003
Tan Li, Zhou Zhan, Liu Pan, Wen Yuan-Shen, and Bao Yao-Zong
Development and Application of High Performance Quenched and Tempered Wear Resistant Steels in Material Handling and Construction Machinery ............................................................................................1011
Fenwei Su and Evangelos Sidiras
Effect of Deformation Parameters on Ferrite and Pearlite Non-Quenched and Tempered and Tempered Steel ....................................................................................................................................................1019
He Yigui, Man Tinghui, Tan Li, Liu Pan, Wei Yuansheng, and Bao Yaozong
Experimental Research and Application of Vanadium Micro-Alloyed Steels in Railway Axle .........................1027 Liu Xingui, Wu Yi, and Xiang Bin
Offshore engineering steels
Strengthen-Mechanism and Corrosion Resistance of Niobium Added HSLA Weathering H-Beams Processed by Ultra-Fast Cooling Process ...........................................................................................................1037
Hao Yu, Hailong Zhou, Houxin Wang, Xiaohui Mao, and Xingjun Li
Microstructure Evolution in the V-N-Ti and Nb-V-Ti Microalloyed Bulb Flat Steel .........................................1045 Chai Feng, Xue Dong-Mei, Yang Cai-Fu, and Su Hang
Corrosion Behavior of New Cr-Ni-Cu Low Alloy Seawater Corrosion Resistant Steel .....................................1055 Piaopiao Zhang, Zhongmin Yang, Ying Chen, and Huimin Wang
Development of High Plasticity-Toughness Low Cost Microalloyed Submarine Pipeline Steel .......................1063 Sheng-Fu Yuan, Xiu-Chen Li, and Cheng-Jia Shang
Precipitation Behavior of Carbon-Nitrides in Microalloyed Offshore Platform Plate .......................................1071 D.I. Guo-Biao, Shen Qin-Yi, Liu Mei-Yan, Jia Tao, Ma Qing-Shen, and Liu Zhen-Yu
Microdomain Yield Behaviour in an Ultra-High Strength Low Alloy Steel for Marine Use with Low Sensitivity of SCC ......................................................................................................................................1079
Yin Jiang, Tao Anxiang, Xu Pingguang, and Ping Dehai
xiiixiii
Effects of Heat Treatment on Microstructure and Mechanical Properties of V Microalloyed Bulb Flat Steel.....................................................................................................................................................1087
Chen Xue-hui, Yang Cai-Fu, Su Hang, Chai Feng, Zhang Qian, and Hou Yaqing
The Use of Model Systems Based on Fe-30 Wt%Ni for Investigating the Precipitation and Transformation Behaviour of Microalloyed Austenite .......................................................................................1095
EJ Palmiere
Development of New Type Seawater Resistant Steel and the Research of Its Structure and Corrosion Resistance ..........................................................................................................................................1103
Baoliang Yin, Shaojiang Yin, Zhiyong Liu, Yunge Wang, Hao Yu, Haixu Li, and Tao Zhou
Development of Technological Methods of Additional Grain Refinement for Production of Cold Resistant Nb-Bearing Plate Steel with SMYS 450-485 MPa and Thickness up to 40 Mm .......................1109
M.Yu. Matrosov, S.V. Golovin, D.A. Ringinen, V.I. Ilynsky, S. Yu, Nastich, A.A. Kichkina, and I.V. Lyasotsky
Microstructure Evolution and Mechanical Properties of Grade E690 Offshore Platform Steel .........................1117 Shuai Qin, Renbo Song, Wenming Xiong, Zhijun Liu, Zhonghong Wang, and Ke Guo
Effect of Cu and Ni on Corrosion Resistance of Low Alloyed Steels for Cargo Oil Tank .................................1125 Luo Xiaobing, Chai Feng, Su Hang, Yang Caifu, Li Hao, Hou Yaqing, and Zhang Zhengyan
Development of Low Temperature Inverted Angle for LPG Carrier Using Slab ................................................1133 Wonchul Doo, Chulwon Lee, and Sungkyu Cho
Research and Development of Micro-Alloying High-Strength Shipbuilding Plate ............................................1141 Zhenye Chen
Effects of Inclusions and Their Surface Chemistry on Cleavage Fracture in a C-Mn Steel Weld Metal ..........................................................................................................................................................1149
Pifeng Miao and John F. Knott
Influence of Nitrogen Addition on Transformation Behavior and Mechanical Properties of Vanadium Microalloyed Steels ...........................................................................................................................1163
Jiangnan MA, Ruizhen WANG, and Caifu YANG
Corrosion Performance of High Strength Weathering Steels Under Different Heat Treatment States ...............1171 Wang Yue, Liu Zili, Liu Xiqin, Zhang Shoudong, and Tian Qingchao
Effect of Ultra-Fast Cooling on Microstructure and Properties of High Strength Steel for Shipbuilding ..................................................................................................................................................1179
Cheng Zhou, Qibin Ye, and Ling Yan
Research and Development of Heavy Wall DNV485FDU Pipeline Plate for 3500M Deep Water Pipe Applications at Shougang ...................................................................................................................................1187
Wenhua Ding, Shaopo Li, Jiading Li, Qun Li, Tieqiang Chen, and Hai Zhang
Preparing of Ni-Cu-P Coating ............................................................................................................................1195 Kang Shumei
Effect of Copper Alloy Element on Corrosion Properties of High Strength Mooring Chain Steel ....................1201 H.P. Shen, X.Y. Cheng, H. Li, S.Y. Zhang, and L.C. Su
Effect of Boron Microalloying Element on Susceptibility to Hydrogen Embrittlement in High Strength Mooring Chain Steel ...................................................................................................................1211
H. Li, X.Y. Cheng, H.P. Shen, L.C. Su, and S.Y. Zhang
Author Index 1219
Subject Index 1225
xv
PREFACE
This is a collection of manuscripts presented at the joint conference of the 7th International Conference on High Strength Low Alloy Steels (HSLA Steels 2015), the International Conference on Microalloying 2015 (Microalloying 2015) and the International Conference on Offshore Engineering Steels 2015 (OES 2015), which is co-organized by The Chinese Society for Metals (CSM) and Chinese Academy of Engineering (CAE), and held in Hangzhou, Zhejiang Province, China on November 11th–13th, 2015.
The conference focused on the exchange of the latest scientific and technological progresses on HSLA steels, microalloying steels and offshore engineering steels over the past decades, strengthen cooperation between universities and research institutes, iron and steel companies and users, and promote the further development in the fields all over the world.
The conference proceedings consist of 10 keynote papers and 141 invited and regular papers. We would like to express our sincere thanks to all the contributors. After the Plenary papers, the manuscripts collected in this collection are divided into the following six parallel sections: Physical Metallurgy; Process Metallurgy; Automotive Steels; Energy Steels; Engineering Machinery, Construction and Transportation Steels; and Offshore Engineering Steels.
It is our hope that the joint conference of HSLA Steels 2015, Microalloying 2015 and OES 2015 can promote and will further promote the research and development of the HSLA steels, microalloyed steels and offshore engineering steels.
ZHAO Pei (CSM) Conference Secretary-General
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ACKNOWLEDGEMENTS
The Chinese Society for Metals (CSM) would like to take this opportunity to express our gratitude to the following contributors. First, we would like to express our gratitude to Chinese Academy of Engineering (CAE) for their great support. Second, we would like to offer many thanks to the conference chairman, vice chairman, conference committees, secretary-general, and vice secretary-generals for their tremendous work in the recommendation of keynote/invited presentations, selection of the papers, promotion of the conference, and participations. They include:
Conference Chairman WENG Yuqing - The Chinese Society for Metals (CSM), China
Vice-Chairman ZHANG Xiaogang - Ansteel Group Corporation, China
Conference Secretary-General ZHAO Pei - The Chinese Society for Metals (CSM), China
Vice Secretary-General YANG Caifu - China Iron & Steel Research Institute Group (CISRI), China SHANG Chengjia - University of Science & Technology Beijing (USTB), China GUO Aimin - CITIC Metal, China
International Advisory Board: Wolfgang BLECK - RWTH Aachen University of Technology, Germany Pascoal J.P. BORDIGNON - Companhia Brasileira De Metalurgia E Mineração (CBMM), Brazil FU Junyan - CITIC Metal, China Anthony J. DEARDO - University of Pittsburgh, USA Carlos GARCIA-MATEO - CENIM, Spain J. Malcolm GRAY - Microalloyed Steel Institute United States of America, USA HAN Enhou - Institute of Metal Research, Chinese Academy of Science, China HE Xinlai - USTB, China Sung-Joon KIM - POSTECH, Korea LI Helin - Tubular Goods Research Institute of China National Petroleum Corporation, China David MILBOURN - Vanitec Limited, UK John SPEER - Colorado School of Mines, USA Marcos STUART - CBMM, Brazil WANG Zubin - CISRI, China XIE Xishan - USTB, China ZHOU Lian - CAE, China
Technical Committee: DONG Han - CISRI, China FU Jianxun - Shanghai University, China HUANG Mingxin - The University of Hong Kong, HK, China Steven G. JANSTO - CBMM North America, USA
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JIN Xuejun - Shanghai Jiaotong University, China KANG Yonglin - USTB, China Philip KIRKWOOD - Cresswell Consultants Limited, UK LI Lin - Shanghai University, China LIU Guoquan - USTB, China LIU Qingyou - CISRI, China LIU Xianghua - Northeast University, China LIU Zhenyu - Northeast University, China LU Jiangxin - Baosteel Group Corperation, China MAO Xinping - Wuhan Iron and Steels (Group) Corperation (WISCO), China Devesh MISRA - University of Texas at El Paso (UTEP), USA Hardy MOHRBACHER - NiobelCon bvba, Beljum Jose-Maria RODRIGUEZ-IBABE - The Centro de Estudios e Investigaciones Técnicas de Gipuzkoa (CEIT), Spain Colin SCOTT - Canmet Materials, Canada Kleber SERNIK - Strategy Consulting,LLC, USA SU Hang - CISRI, China YANG Jer-Ren - National Taiwan University, Taiwan, China YANG Zhigang - Tsinghua University, China YONG Qilong -CISRI, China ZHANG Hongtao - CISRI, China ZHANG Wanshan - Ansteel Group Corperation, China Organizing Committee: FU Lianchun - WISCO, China HOU Angui - Baosteel Group Corperation, China LIU Nan - Anyang Iron and Steel Group Co., Ltd, China MENG Fanying - Baotou Iron and Steel (Group) Co., Ltd, China SU Shihuai - Maanshan Iron and Steel Company Ltd, China TIAN Zhiling - CISRI, China WANG Lixin - Taiyuan Iron and Steel (Group) Co., Ltd (TISCO), China WANG Xindong - Hebei Iron and Steel Group, China XU Jiayan - Benxi Iron and Steel (Group) Co., Ltd, China YU Zisu - Ansteel Group Corperation, China ZHANG Shengsheng - Laiwu Iron and Steel Group, China ZHANG Xiaobing - Shagang Group Coperation, China ZUO Liang - Northeast University, China
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Engineering Steels 2015 CONFERENCE PROCEEDINGS
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ZHANG Xiao-gang 1, YANG Cai-fu 2, SHANG Cheng-jia 3
1. The Chinese Society for Metals, Beijing, PR China; 2. Central Iron and Steel Research Institute, Beijing, PR China;
3. University of Science and Technology Beijing, Beijing, PR China
Keywords: HSLA steel, microalloying technology, China’s iron and steel industry
Abstract
During the last decade, the adjustment and upgrade of steel product structures always be very important tasks in China’s iron and steel industry. Since there is a fast growth of steel production in China, a series of research achievements in the technology area of HSLA steels have been made and applied successfully in the actual production, and thereby promoted a rapid development and application of China’s HSLA Steel products. However, The China’s iron and steel industry is now facing the excess production capacity and under pressure from respects of resource, energy and environment, therefore, it would be an effective way to realize the sustainable development in China’s iron and steel industry by strengthening the applications of HSLA steels continuously and positively.
Changes of Product Structure in China’s Iron and Steel Industry
The history data on China steel production and consumption was given in Table 1. There was a tremendous growth in China crude steel production and consumption during the last decade. Figure 1 shows more clearly the growing trend of China iron and steel industry. As shown in Fig.1, the production and consumption of China crude steel are respectively 128 and 142 million tons in 2000, and the figures have increased to 822 and 773 million tons till 2013. However, there was an obvious change in China iron and steel industry in last year. 2014 China crude steel production is 822.7 million tons, and only 0.9% year-on-year growth rate, which is the lowest point compared with the past three decades. Moreover, the apparent consumption of China crude steel had started to fall in 2014, and there was about 3.4% decrease compared with the figure in 2013. With the increase in crude steel production, the steel product structure in China had also a big change. As revealed in Table 1, in 2005, the total production of China crude steel was 305 million tons, incl. 233 million tons of carbon steel production which occupies 65.36% of total production, 103 million tons of low alloy steel which is 28.84% of total production, and 20.63 million tons of alloy steel (stainless steel included) which occupies the rest 5.80%. And till 2013, the total production of crude steel in China had increased to 822 million tons, and among these, the production of carbon steel was about 486 million tons and its ratio in total crude steel production decreased to 59.11%, and the production of low alloy steel reached to 275 million tons and the proportion increased to 33.51%, and alloy steel (stainless steel included) production was 60.63 million tons and occupied the rest 7.38%. Viewed the change
HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015 The Chinese Society for Metals (CSM) and Chinese Academy of Engineering (CAE)
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of the history data on China steel product structure as shown in Fig.2, it can be seen clearly that the carbon steel occupied all the time dominant position in the whole China steel product structure before 2000 and the proportion can reach 70%-80%, while the proportion of low alloy steel (include C-Mn steel) is low than 15%; but during last decade, the proportion of the carbon steel has reduced to the level below 60%, while the proportion of the low alloy steel has a significant increase recently, and reaches to 33% till 2013.
Table 1 Changes of product structure in China’s iron and steel products during 2005-2014
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Fig.2 Changes of steel product structure in China
Fig.3 shows the outputs variation of China V and Nb microalloyed steels during 2001-2014. It can be seen from Fig.3 that there is a dramatic increase in the total microalloyed steel output in China in past 15 years, and the total V and Nb microalloyed steel output is only about 6 million tons in 2001, however, the output has increased to over 120 million tons in 2014 which is over 20 times of the output in 2001. It is worth noting that there is a fast growth in the production of China V microalloyed steel recent 5 years. The total V microalloyed steel output in China was about 22 million tons in 2009, while the output had reached to 88 million tons in 2014. The fast development of V microalloyed steel makes a great contribution to promote the production of China HSLA steel.
Fig.3 Outputs of V and Nb microalloyed steels in China
The changes of steel consumption in China main industries are shown in Table 2, and the evidence indicates that the consumption of construction steel occupies half more of the total consumption, and what following behind construction is the machinery, the consumption of which could reach 20% of the total consumption. With the fast growth in China automobile industry, the consumption of automobile steel continues to grow and the proportion increases to about 7%.
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In fact, all China main industries, including construction, automobile, household electronics, shipbuilding, pipeline, bridge construction, container, machinery and high speed rail, etc., kept a rapid growth recently, and this had exactly a great contribution to the development and application of HSLA steel in China, as shown in Fig.4.
Fig.4 Production of flat products in China by use during 2009-2013
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Latest Development of Physical Metallurgy in China
Microalloying Technology and TMCP Process Enhanced-N in V steels promotes precipitation of fine V(C,N) particles, and improves markedly precipitation strengthening effectiveness of V(C,N), therefore, there is a significant saving of V addition in a given strength requirement. V-N microalloying can be also used effectively for ferrite grain refinement as well by the nucleation of intra-granular ferrite promoted by VN precipitates in Austenite in V-N steels. With the combination of the technology of intragranular ferrite (IGF) on VN particles and the recrystallization controlled rolling (RCR), a new controlled rolling technology has been developed in China and named as V(C,N) Precipitation Controlled Rolling Process (VCN-PCRP), as illustrated in Fig.5 which realizes ferrite grain refinement in V microalloyed steels. V-N microalloying process has been widely used for high strength rebars, section steels, forging steels, seamless pipes, and CSP strip steels in China.
Fig.5 Schematic illustration of VCN-PCRP process
High Temperature rolling process (HTP) with the alloy design of high Nb had been successfully applied on the development of heavy X80 pipeline steel plate and strip with thickness of 18.4mm and 22.4mm which has been fully used for the construction of the west-east gas pipeline project. The experimental research results in Fig.6 indicate that austenite refinement, especially enough flattening after rolling process, plays an important role in controlling DWTT properties. In high Nb pipeline steels, the grain size of prior austenite can be refined into less than 20 m during recrystallization rolling process. When the refined austenite is further flattened during the non-recrystallization process, the fine acicular ferrite can provide fine toughness and low DWTT. As for special heavy plates, fine low temperature toughness can also be obtained by refining the austenite in the middle of plate.
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Fig.6 Effect of the pancaked austenite height on DWTT properties in pipeline steel
In order to solve the problems of low temperature rolling and addition of microalloyed elements in a traditional TMCP technology, the new generation TMCP (NG-TMCP) technology based on ultrafast cooling (UFC) has been developed in China. The core concept in NG-TMCP includes: 1) to achieve the strain accumulation in austenite during the continuous rolling at relatively high rolling temperatures; 2) ultra fast cooling after rolling to keep the work hardening of austenite; 3) to stop cooling temperature around transformation temperature; 4) to control the cooling route according to the requirements for microstructure and properties of steel, as shown in Fig.7. So far, this new technology has been widely used in China 31 hot rolling production lines for hot strip mill, plate mill, wire rod mill and applied to develop a series of high strength low alloy steel, automobile steel, pipeline steel, etc.
Fig.7 The comparison between NG TMCP and conventional TMCP
Advanced High Strength Steel Technology Multi-microalloyed with V, Mo and Ti technology in low C Mn steel base was successfully used to develop 900 MPa ultra high strength ferritic steel. The multi addition of V, Ti and Mo in steel can not only increase the volume fraction of nano-scale MC particles, but also
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significantly inhibit MC particles coarsening, and thus the particle size could be refined remarkably. As shown in Fig.8, over half of MC particle sizes were less than 5 nm in diameter, and over 90% of the mass fraction of MC particles were less than 10 nm. As a result, more than 400 MPa increment of precipitation strengthening, almost twice than that of conventional microalloyed steel, was obtained with 0.5 wt% V-Ti-Mo microalloyed steel.
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Fig.8 Nano-scaled (Ti,V,Mo)C precipitation and ferrite grain size in V-Ti-Mo microalloyed steel
Low carbon bainitic technology with the alloy design of Mn-Mo-Nb-V has been used in the development of X90-X120 grades pipeline steel in China. In 0.05%C-Mn-Mo-Nb-V X100 pipeline steel, the good combination of high strength and toughness can be guaranteed by fine bainitic microstructure with disperse M-A islands on the matrix in hot rolled plate products
which have reached 725MPa yield strength and 350J of impact toughness at -20 .
The alloy design of medium-Mn steels with different carbon contents processed by austenite reverted transformation (ART-annealing) fabricated the ultrafine duplex steels with large fractioned austenite which was given as one of the optimum structures to develop the third generation automobile steel with high strength and high ductility. The duplex structure with large fraction of austenite and ultrafine grain structure is capable of producing steels with excellent combination of strength and ductility, i.e., Rm×A about 30–50 GPa%, which is about two times of that of the conventional automobile steels and close to that of the TWIP steels, as shown in Fig.9. The experimental research results revealed that the ART-annealing of the medium-Mn steels would be at least one of the promising ways to fabricate the third generation automobile steels in the near future.
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Fig.9 The development of 3rd generation automobile steel with alloy design of medium Mn High Heat Input Welding Technology Using Ti-Mg and Ti-Zr microalloyed technology, the size and distribution of Ti oxides can be effectively refined and altered, which can dramatically improve the CGHAZ toughness under the high heat input welding condition. As shown in Fig.10, when the heat input varies from 20 to 200 KJ/cm, the simulated CGHAZ toughness of Ti-Mg microalloyed experimental steel could be kept on a relatively high level, and that is mainly because the formation of intragranular ferrite promoted by oxides.
Fig.10 Effect of microalloying technology on simulated CGHAZ toughness
Development and Application of HSLA Steel Products in China Construction Steels More than half steel consumption in China is used in construction industry, and reinforcing bars, as the biggest steel products in China, take about one-fourth of the total steel production. Recently, there is a dramatic growth in production and consumption of hot-rolled rebars in
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China as fast development of the national building industry, as shown in Fig.11, the total rebars production has reached to 215 million tons in 2014. It is specially worth to mention that there is also a significant change in China rebar product structure in past decade. As shown in Fig.11, the grade 2 rebar with yield strength 335MPa takes up 80% building market share 10 years ago, however, the proportion has been reversed right now, and the production of high strength rebar (Grade 3 over) has reached to 72% till 2013. The upgrade of building rebar has undoubtedly promoted the fast development and application of HSLA steels in China.
Fig.11 Changes of Production and products structure for China rebars steels last decade
Automobile steel There is a very rapid growth in China automobile industry last decade, which contributed to the research, development and application of automobile steel in China. The latest statistical analysis shows the output of automobile reaches 23.72 million in 2104, and it promotes the
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production of automobile steels in China to reach to about 46.50 million in 2014, as seen in Fig.12.
Fig.12 Changes in Vehicle production and automobile steel production in China
The changes of automobile steel products in China is far more than the rapidly growth of output. Today, a series of advanced high strength automobile steels (AHSS), incl. high strength IF steel, BH steel, DP steel and TRIP steel, etc., have been successfully developed and produced in most China automobile steel producers, and these AHSS products have also been widely used in China automobile industry. At present, the proportion of high strength automobile steel in China has reached 40% in 2014, and the application of coated steel in China automobile industry has increased to 45% in 2014, as shown in Fig.13.
Fig.13 the proportion of high strength steel and coated steel in China automobile steel Pipeline Steels In recent years, the oil and natural gas pipelines are being constructed massively to meet the strong needs of rapid clean energy development in China, as shown in Fig.14. The
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development of long-distance transmission pipelines such as the 2nd and 3rd west-east natural gas pipelines and the China-Myanma pipeline have improved the level of manufacturing and construction of high grade pipeline steel in China. And two planned projects, i.e. the SINOPEC’s synthetic natural gas (SNG) high pressure pipeline project and the China-Russia East large diameter X80 pipeline project will present new challenges on the development of pipeline steel.
Fig.14 Change of China Pipeline Steel Production during last decade
The second and the third west-east gas pipeline projects are the longest in terms of single line among all high pressure X80 gas pipeline projects in the world. Both projects used spiral submerged arc welded (SSAW) pipe with 1219mm in diameter and 18.4mm in wall thickness for the first time, which was very difficult in techniques. Through in-depth studies on strengthening and toughening mechanisms of heavy gauge X80 plate/strip, the technical route that combines both high niobium microalloying and TMCP to realize microstructure refinement through the whole process was developed to produce X80 strip with 18.4mm in thickness and X80 plate with 22-33mm in thickness. The developed X80 steel pipe has excellent properties in strength, toughness and weldability. X90/X100 ultra-high strength pipeline steel is now being developed in China in order to further improve the transmission efficiency and reduce the construction cost of pipeline, and
great progress has been made in this aspect. In present, the CVN values at -10 of the
trial-production ultra-high strength steel pipe can be stably controlled in the level of more than 280J, and the construction of a test section is now being planned in China. Furthermore, X80 strip of 21-22mm in thickness used in large diameter X80 SSAW pipes has been trial produced successfully, and will be applied in the China-Russia east pipeline project soon. Important progress has also been made on the strain based design pipeline steel. The high
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deformable pipeline steels of X70 grade with 17.5-21mm in thickness and X80 grade with 26.4mm in thickness have been developed successfully and used in the China-Myanma pipeline and the third west-east pipeline projects. As for the deep-sea pipeline steel, the developed X70 grade steel plate with 31.2mm in thickness has been applied in the China’s first 1500m ultra-deep water pipeline project. Also, X70 grade ultra-deep water steel pipe with OD914 36.5mm has been trial-produced successfully under the support of national 863 project of China. Shipbuilding and Offshore Steels China's shipbuilding industry has entered into a new rapid growth in the new century. In 2014, the completion, new orders and handheld orders of China's shipbuilding accounted for 41.7%, 50.5%, 47.1% of the total world share respectively, and undoubtedly China is the No.1 shipbuilding country in the world. Fig.15 shows that the rapid development of China's shipbuilding industry promotes the production of shipbuilding plate steel in China significantly, and the production of China shipbuilding steel has reached a peak at 22 million tons in 2011, but unexpected global economic crisis causes a strong impact on China's shipbuilding industry, led to the subsequent decline of shipbuilding completion. It can been seen that 2013 production of China shipbuilding steel has descended to a low point with 11 million tons, only half level in 2011. Fortunately 2014 China shipbuilding steel production rebound to13 million tons, and seems to be some recovery in China shipbuilding industry.
Fig.15 Development of shipbuilding industry and shipbuilding steels in China
In all of shipbuilding steel, high strength shipbuilding steel plate (32, 36 and 40kg) has become the main products in China's shipbuilding steels. In order to satisfy the development requirement of China shipbuilding and offshore engineering industry, a series of higher strength steels with 440MPa, 460MPa, 550MPa and 690MPa, etc., have been developed and applied in the actual engineering construction in China. At present, 178mm ultra heavy plate with 690 MPa for Jack-up platform has been developed in China. In order to meet the requirement of high efficiency on welding process, high strength shipbuilding plate with high
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heat input (~200KJ/cm) has also been successfully developed and applied in China. Recently, International Maritime Organization (IMO) approved Standard of corrosion resistant steel for COT of oil tank and it was enforced since January 1, 2014. R&D of the new anti-corrosion steel for the application of COT had been completed in China and the industrial anti-corrosion steel had been successfully used to fabricate a demonstration project of oil vessel with the max deadweight of 50,000 MT.
Conclusion China’s iron and steel industry is now facing the big pressure from over-capacity, shortage in resource and energy, and environmental protection. The development of HSLA steel is a cost-effective way to overcome these problems. In order to maintain the sustainable development of China's iron and steel industry, it will be the long-term task to promote the upgrade of steel products and adjust steel product structure in near future. The upgrade of China manufacturing industries offers a good opportunity for China steel industry to develop and promote the application of HSLA steels. It is the most important to expand the application of HSLA steel that is needed to strengthen the close cooperation in research, production and application in the whole industrial chains. In addition, there are very rich V and Ti resources in China, and it creates a good condition for us to promote the technical research, development and application of V and Ti microalloyed steel in China.
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Anthony J. DeArdo
Director of Basic Metals Processing Research Institute Department of Mechanical Engineering and Materials Science
Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA And also
Finland Distinguish Professor Department of Mechanical Engineering
University of Oulu
Abstract
The role of microalloying has changed over the years as the range of products where used has expanded and the production processes have improved. When used in the early ferrite-pearlite steels, its chief function was grain refinement and precipitation hardening. Later, as the quest for higher strength led to bainitic and martensitic microstructures, the role of microalloying changed to grain refinement and transformation control. Later still microalloying has been successfully applied in martensitic and the advanced high strength steels grades for automobiles. The goal of this paper is to follow this changing role of microalloying in both conventional and advanced steels from the 1960s until today.
Introduction
Although there has always been a demand for high strength flat rolled steel, the interest in higher strength steels increased in the 1970s as a result of the global economic dislocation caused by the Oil Embargos in the Middle East. The development of modern microalloyed HSLA steels began in the early 1970s when the world suffered the first of two crises in its oil supply from the Middle-East. These events led to a quadrupling of the crude oil prices on oil imported from that area, and resulted in a decade-long abnormal increase in oil prices. This disruption had a large impact on the global economy and the steel industry, in particular. Whereas the concepts of downsizing or light weighting were an afterthought in steel usage in the 1960s, they became the mantra of the steel industry after the Oil Embargo of 1973.
Prior to 1973, the global steel industry produced mainly lower strength ferrite-pearlite steels for general use and small amounts of martensitic heat treated steels when higher strengths and hardness were required. However, after the price of oil skyrocketed, much attention was focused on downsizing and light weighting by practically every industry, but most particularly in the transportation industries, construction and of course in the oil industry. However, downsizing and light weighting can only occur by the use of higher strength steels, where thinner gages can be used. Heat treated steels were not the answer as the heat treating facilities were rather limited, and being a batch process, further limited productivity. The answer was high strength hot rolled steel, where the steel had the required properties after being cooled or coiled to room temperature, e.g., with YS > 420MPa. These hot rolled steels could be produced efficiently in large tonnages. The central question at that time was how to produce high strength hot rolled steels without heat treatment. As is now well-known, these steels also had to be strong, tough and weldable.
HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015 The Chinese Society for Metals (CSM) and The Chinese Academy of Engineering (CAE)
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HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015 The Chinese Society for Metals (CSM) and The Chinese Academy of Engineering (CAE)
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HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015 The Chinese Society for Metals (CSM) and Chinese Academy of Engineering (CAE)
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Since the early plate mills had mainly only air cooling after rolling, the early steels had ferrite- pearlite microstructures with modest strengths at 12-20mm gauge as discussed above. As the operating pressures and pipe diameters continued to increase, and the wall thickness decrease, the stresses in the pipe wall also increased. This required the use of even higher strength steels.
Research over the past half-century has led to the availability of steels with YS ranging from 350 to 1000 MPa for use in the transportation, construction and energy industries. This paper attempts to document some of the milestones on the road from simple C-Mn-Si hot rolled steels of the 1960s with ferrite-pearlite (F-P) microstructures to the modern bainitic, martensitic and multi-phase steels of today and tomorrow. Much of this improvement has been enabled by improvements in steelmaking, hot rolling and cooling technologies, but equally important has been the critical role of microalloying in this evolutionary development.
Microalloying and Ferrite-Pearlite Steels in the Strength Range of YS 350-500 MPa
After nearly a half-century of research, it is now clear that microalloying additions play several roles in all HSLA, but in particular in those steels with ferrite-pearlite microstructures. Their chief function is to control: (a) austenite conditioning for grain refinement, (b) lower the transformation temperature, and (c) possibly cause precipitation hardening. They do so by controlling the critical temperatures of the austenite such that they can be adjusted to meet the characteristics of the processing equipment and also the properties of the final product. These critical temperatures are: (i) the grain coarsening temperature during reheating, (ii) the recrystallization stop temperature during hot rolling and (iii) the transformation temperature during cooling [1-3]. These effects are shown schematically in Figure 1 superimposed on the Fe- Fe3C phase diagram.
Figure 1. Fe-C phase diagram, with critical temperatures indicated
The transformation temperature of a steel is governed by its hardenability or CCT diagram and the operative cooling rate. When this temperature is above 650C with steels of moderate Mn content, the resulting microstructure is ferrite-pearlite. It is well-known that the strength of F-P steels can be expressed by the expanded Hall-Petch equation [4], where the grain size effect and the precipitation hardening increment are dominant. An example is shown in Figure 2. Plain
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carbon steels with polygonal ferrite-pearlite microstructures and with a ferrite grain size of approximately 6 microns, should have a YS of about 400 MPa and a UTS of approximately 500 MPa, while a microalloyed steel of similar grain size might have a YS higher by 100MPa. Even higher strengths are achievable if the ferrite is quasi-polygonal or slightly acicular in nature, or if there is a significant contribution from precipitation hardening.
Figure 2. Experimental Hall-Petch relationships as determind by quantitative metallograph for carbon-manganese and carbon-manganese-nioblum steels.
Microalloying and Austenite Conditioning Since the as hot rolled austenite grain size is so critical to the final microstructure, strength and toughness of MA HSLA steels after cooling, a good portion of the early research was focused on this aspect. A critical contribution to this area came from Kozasu who showed in 1975 that the effectiveness of the austenite grain structure can be indexed by the grain stereological parameter Sv [5]. The higher the Sv, the more grain boundaries and deformation bands per unit volume, and the more effective the austenite would be in nucleating ferrite and also in stopping the growth of cleavage cracks. The crystalline defects that comprise the Sv are shown in Figure 3 and the effect of Sv on FGS is shown in Figure 4 [6].
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Figure 3. Dark field optical micrograph of nucleation of ferrite at deformed austenite
grain boundaries, deformation bands (A), and annealing twins (B).
Figure 4. Ferrite grain sizes produced from recrystallized and recrystallized
austenite at various Sv values. It was shown that the role of microalloying in increasing Sv was to generate retarding forces that would slow or stop the static recovery or recrystallization that would otherwise occur between passes in the rolling mill. For plate mills with many light passes and long interpass times, the MA acted to suppress recrystallization by forming strain-induced precipitates that could pin the grain and subgrain boundaries. However, for strip mills with fewer, heavier passes and short interpass times, the MA would act to suppress recrystallization by exerting solute drag on the dislocations and sub-grain boundaries. Both Nb and V can be useful in this regards, although they do so over different temperature ranges, due to their different solubility products. The guiding principle learned from this early work is that the recrystallization stop temperature T5, as defined in Figure 5, can be controlled through microalloying and the MA addition should be selected to match the rolling practice of interest for the case of plate rolling[7]. The pancaked
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grains that result from deforming below T5 are shown in Figure 6 for VAN steel [8]. The strain- induced precipitate responsible for the pinning force that had suppressed static recrystallization is shown in Figures 7 and 8, for V steel [8] and Nb steel [1], respectively.
Figure 5. T vs strain + CCT for pptn curve
Figure 6. Optical micrograph of V steel hot rolled 50%, held 3 minutes at 1600°F, WQRT [5]
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Figure 7. Dark field TEM micrograph taken with 110V(CN) spot showing V(CN)
precipitates on the subgrain boundaries of the prior austenite. Sample hot rolled 50% at 1600°F (871°C) and held 12 minutes, then air cooled to room temperature.[5]
Figure 8. Strain induced precipitation of NbCN in austenite in a steel containing 0.09%C - 0.07%Nb. Specimen reheated at 1250°C, rolled 25% and held at 950°C, and air cooled
to RT. Centered dark field electron micrograph using a (111) NbC reflection. After Santella, 1981.
However, knowing the tenants of the basic physical metallurgy is not the same as understanding how to use the knowledge in a steel plant. Fortunately, this era also produced some important diagrams that could be used in a practical sense to improve the MA HSLA steels, both in their compositions and their processing. The first of these is how the recrystallization stop temperature T5 can be controlled or pre-selected for a given steel or rolling mill. It was shown that the T5 temperature can vary with different MA precipitation systems in plate rolling experiments, Figure 9 [9]. This diagram illustrates how the T5 temperature can be pre-selected based on the steel, rolling process and the level of microalloying needed.
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Strength of Ferrite– Pearlite Microalloyed HSLA Steels
It is obvious from Figure 2 that the ferrite grain size makes a significant contribution to the strength of ferrite-pearlite steels. Although other strengthening mechanisms have been identified, e.g., solute hardening, texture hardening and dislocation hardening, only precipitation hardening was shown to be important in ferrite-pearlite microstructures. Research over thirty years from that era to the present showed repeatedly that there can be two forms of precipitates formed in ferrite leading to precipitation hardening, interphase precipitation at higher temperatures and slower cooling rates (10RWKH, 11Kirst, 12Todd, 13 Gao, 14Sweden, 15Spain), Figure 10 for a V steel (16Batte) and Figure 11 for a Nb steel (17Santella). However, general precipitation occurred in ferrite formed and held at lower temperatures, e.g., slow cooling from the water end temperature for rapidly cooled plates or lower coiling temperatures for strip. (11Sakuma, 12Kirsti, 18Cryderman, 14Sweden, 15Spain).
Figure 10. Bright field TEM of Interphase VCN in ferrite at 725C, Fe-0.75V-0.15C
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Figure 11. Interphase precipitation of NBCN in ferrite in steel containing 0.09%C - 0.07%Nb. Specimen was reheated to 1250°C, hot rolled to 1000°C and air cooled to RT. Bright field electron micrograph. After Santella, 1981.
Guidelines for selecting the overall composition of a steel for a given application including strength, toughness and weldability were also published at this time, and have been reviewed [1- 3]. In summary, ferrite pearlite microstructures of microalloyed HSLA steels can achieve yield and strengths from 280 to about 500 MPa. in reasonable gages with good toughness and weldability.
Pathway to high strength steels The route to higher strengths beyond those available with ferrite-pearlite microstructures was presented by Irvine and Pickering in the late 1950s, when they showed how the strength of bainitic steel was related to the transformation temperature, Figure 12[19].
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Figure 12. Effect of temperature of maximum transformation rate on tensile strength in a series of alloys with a base composition containing 0.5%Mo and
0.002%B. Cooling rate was typical of those obtained during air cooling of a 19 mm-diam bar. (irvine and Pickering)
Figure 13. Evolution of plate steel for large diam. linepipe: microstructure and properties.
A similar concept was later presented in the context of plate rolling, Figure 13[20] To reach higher strengths, the transformation temperature must be lowered by alloying and water cooling in the case of plate as shown in Figures 12 and 13, or by lowering the coiling temperature in the case of strip. For strip mill simulations, the influence of Mn-Cr-Mo-V were studied on the Bs and Bf temperatures during continuous cooling at 30°C/s, Figure 14 [21]. It is clear that the addition of V had a small effect on these temperatures and a larger effect in the presence of higher N. Although the effect of the V or V-N on the Bs was not large, the resulting effect of coiling temperature on strength was quite impressive, Figure 15 [21].
The influence of alloying on the Bs and Bf temperatures in bainitic strip steels containing V or V-N is shown in Figure 14 [21]. There is more of a slope to the BS and Bf lines in the Cr-Mo-V steel CCT diagrams, Fig.8. It is interesting to note that the addition of V or V-N to a 0.04C-1.3Mn-Cr-Mo steel had little apparent effect on the transformation temperatures, BS and Bf, Fig.9, but did have a significant effect on mechanical properties when viewed from the coiling temperature in a ROT simulation, Fig.10 [21].
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Figure 14. Effect of Cr, Mn, Mo, V, Al and N on transformation characteristics of deformed specimens during cooling at 30°C/s from 900°C to RT. The upper curve is the start temperature and the lower the finish temperature [21].
Figure 15. Yield stress versus coiling temperature for the steels with standard contents of 1% Cr and 0.25% Mo. Results for continuous cooling at 30°C/s to RT are also shown [21].
High Strength Bainite
In an attempt to reach yield strengths over 690 MPa in heavier plates, a steel of high C.E.(~0.5) and Pcm(~0.21) was investigated [22 – 24]. The composition is shown in Table 1.
Table 1. Steel Composition, wt% C Mn P S Si Cu +Ni +Cr+Mo Ti Al N Nb B
0.06 1.89 0.009 0.0016 0.29 1.25 0.01 0.023 0.0046 0.039 0.0005 This steel was controlled rolled and then water spray cooled at 10C/s to either 400C (Steel B1) or 500C(Steel B2), then ACRT. The two specimens had similar tensile properties, but steel B1 had a DBTT of -60C while steel B2 showed -20C. The metallography conducted to help explain the difference in low temperature toughness revealed several important differences. First, the crystallographic packet size was smaller in B1 than in B2, Figure 16. Second, the amount and
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size of the MA microconstituent were larger in B1 than in B2, Figure 17. And third, it should also be mentioned that given sufficient time, the repartitioning of carbon can occur leading to the reformation of austenite during the bainite reaction, resulting in higher carbon fresh martensite to form during the final cool. This untampered martensite is thought to contribute to lower toughness resulting from slower rates of cooling or extended isothermal holding times below the Bs temperature(Oulu, MST14, Met Trans)
(a) B1
(b) B2 Figure 16. The highlighted crystallographic packets (left) and sizes (right) in a) sample B1; and b) sample B2.
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(c) Retained austenite(green
area):10vol% (d) Retained austenite(green area):
8vol% Figure 17. The distribution of MA in samples B1: (left) (a) Image based on LePera etched microstructures, (c) EBSD analyzed retained austenite; and B2: (right) (b) Image based on LePera etched microstructures, (d) EBSD analyzed retained austenite.
(a) (b)
20μm 20μm
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Figure 18. Different bainitic microstructure sizes under different controlled cooling rates detected with EBSD techniques. (a) slow cooling rate; (b) fast cooling rate.
Figure 19. Isothermally treated SEM microstructures.(a) 450°C, 4 minutes;(b) 450°C, 10 minutes.
Microalloying and Zinc-coated Advanced High Strength Steels
Over the past decade, the UTS of high strength dual-phase steels has risen from 590 MPA to 780 MPa commercially and to over 1180MPa experimentally. Much of this increase is due to the addition of Nb and/or V to the base compositions [25-27]. In this current work, 0.06 V, was added to a base composition containing 0.1 C-1.5 Mn plus either a 1.5 Mn - 0.5 Cr - 0.3 Mo or a 1.5 Mn - 0.25 Cr - 0.1 Mo base. It has been shown that the MAE provided four benefits: (i) increase the hardenability of the intercritically-formed austenite, thereby allowing less new ferrite to form on cooling; (ii) reduce the martensite island size, hence increasing the work hardening rate and stretch formability; (iii) strengthen the ferrite, and leading to overall higher strengths; and finally (iv) increase the tempering resistance of the bainite and other types of ferrite formed at 460°C, the temperature of the zinc pot. After intercritical annealing at 790°C and cooling to 460°C using several thermal paths, the strengths of the resulting DP steels are shown in Figure 20.
(a)
α’
α’
(b)
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Figure 20. Strength of Dual Phase Steels using different thermal paths in CGL simulations
Several interesting observations can be made concerning Figure 20. One is that the small vanadium addition had a large effect on the final UTS of up to 66 MPa for the higher alloyed version of the DP steel, and up to 84MPa in the lower alloy version. Another important observation is the obvious importance of the higher levels of Cr and Mo in the higher alloy version. Still another is the higher effectiveness of the V in the lower alloy version than the higher alloy version. The addition of the vanadium led to higher strengths with only a slight lowering of elongation and reduction in area. Finally, the sheared edge ductility or hole expansion ratio properties of the V-bearing steel were similar to the V-free steel, but at higher strength levels in the V steel. The engineering effectiveness of the advanced high strength steels is often given as the product of (UTS, MPa) X (TE, %). The higher the product, the more effective the steel. Using this approach, products falling between 10,000 and 18,000 are considered good DP steel properties, products between 18,000 and 22,000 are considered good TRIP steel properties, and over 22,000 considered Generation III properties. This product is shown in Figure 13 for the two DP steels used in this experiment. For the standard GI process D1, there are two conditions that are Gen III and six that are TRIP level properties. For the supercooled practice E1, there are four conditions with Gen III properties and ten with TRIP steel properties.
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(a) (b)
Figure 21. (UTS x %TE) product data for experimental steels and processes, (a) process D1, (b) process E1. 10K dashed red, 18K dotted blue, and 22K solid green. By convention, 10K < DP < 18K; 18K < TRIP < 22K; and Gen III > 22K.
Summary and Conclusions
Vanadium is a valuable contributor to the performance of ferrite-pearlite HSLA steels. By taking advantage of grain refining and precipitation hardening that it can contribute, the use of vanadium in these products leads to improved strength and toughness. The strength of bainitic ferrite in low carbon steels is directly related to its B50 temperature. Vanadium is a benefit here with its grain refining, solute drag and hardenability contribution. Vanadium increases the strength of Dual-Phase steels with little penalty in ductility. The sheared edge ductility of the V-bearing steels was very good when considering the higher strength level. In the experiments conducted, both the high alloy and the low alloy versions of the DP steels were processed with four different conditions of hot band microstructure(coiling temperature), and cold reduction and were also processed with four different thermal paths following the intercritical anneal. Several processing paths led to both TRIP and Generation III-level properties.
Acknowledgements
The author should like to thank Vanitec, Ltd. for providing financial support for the writing and presentation of this paper.
References 1. A. J. DeArdo, in Microalloying '95, ISS-AIME, Warrendale, 1995, 15. 2. A. J. DeArdo, Ironmaking and Steelmaking, Vol. 28, No. 2 (2001), pp.138-144. 3. A. J. DeArdo, “Niobium in Modern Steels,” International Materials Reviews, Vol. 48, No. 6, (2003), pp.371-402.
700 750 800 850 900 950 1000
5
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V free, Heat treatment D1 With V, Heat treatment D1
UTS (MPa)
15
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V free, Heat treatment E1 With V, Heat treatment E1
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4. A. LeBon et al., Microallying’75, pp90-99 5. I. Kozasu Microallying’75, pp120-135 6. T. Siwecki, et al., Microallying’95, Pittsburgh, ISS, Warrendale, 1995, pp 197-212 7. T vs strain E. J. Palmiere et al., in Low Carbon Steels for the 90’s, edited by R. Asfahani and G. Tither, TMS AIME, Warrendale, 1993, pp121-130, 8. A. J. DeArdo and Mingjian Hua, Vanadium Microalloyed Steels: A Symposium in Memory of Michael Korchynsky, MS & T 2014. 9. L. J. Cuddy, Plastic Deformation of Metals, Academic Press, New York, 1975, pp. 129-140. 10. A. T. Davenport, et al., Met. Sci., Vol2, P104, 1968. 11. K. M. Tiitto et al., in Phase Transformations in Ferrous Alloys, TMS-AIME, Warrendale, 1984, pp. 281-292. 12. J. A. Todd, JOM, V43, 1991, pp. 45-48. 13. W. Gao, University of Pittsburgh, Unpublished Research , 1995 14. R. Lagneborg, et al., The Role of Vanadium in Microalloyed Steels, Vanitec, 2014, pp. 31-45. 15. A. Iza-Mendia, et al., Met Trans A, 2012. 16. A. D. Batte and R. W.K. Honeycombe, J. Iron Steel Inst, V211, 1973, p. 284 17. M. L. Santella, Ph. D. Thesis, University of Pittsburgh, 1981 18. R. L. Cryderman, in Proceedings of the Conference “Toward Improved Ductility and Toughness”, Climax Molybdenum Company of Michigan, Ann Arbor, 1971, pp. 119-142. 19. K. J. Irvine and F. B. Pickering, J. Iron Steel Inst., V187, 1957, p. 292. 20. M. K. Graef et al., in Accelerated Cooling of Steel, TMS-AIME, Warrendale, PA 1986, pp. 165-180. 21. T. Siwecki et al., ISIJ International, V50, 2010, pp. 760-767. 22. X. Liang, “The Complex Phase Transformation of Austenite in High Strength Linepipe Steels and its Influence on the Mechanical Properties”, Ph. D. Thesis, University of Pittsburgh, 2012 23. X. Liang and A. J. DeArdo, in Seventh International Conference on Physical and Numerical Simulation of Materials Processing, 2013. 24. X. Liang et al., “The Design of Microstructure for Strength and Toughness in Low Carbon High Strength Bainite Using EBSD Techniques”, Materials Science and Technology (MS&T) 2014 October 12-16, 2014, Pittsburgh, Pennsylvania, USA, pp.1411-1420. 25. Y. Gong, PhD Thesis, University of Pittsburgh, 2015 26. Yu Gong and A. J. DeArdo, in MS&T 2014, TMS-AIME, Warrendale, PA, 2014 27. Yu Gong and A. J. DeArdo, in Galvatech 2015, TMS-AIME, Warrendale, PA, 2015
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A. Ray and H. K. D. H. Bhadeshia
University of Cambridge Materials Science and Metallurgy
27 Charles Babbage Road, Cambridge CB3 0FS, U. K.
Keywords: rail steel, pearlite, carbide-free bainite, microalloying, niobium
Abstract Rails generally do not have a homogeneous austenite grain structure across their sections because the degree of plastic strain achieved during hot-rolling depends on location. Here we explore a philosophy in which niobium microalloying may be introduced in order to thermomechanically process the material so that pancaked and re ned austenite grains may eventually be achieved in the critical regions of the rail. The essential principle in alloy design involves the avoidance of coarse niobium carbide precipitates in the regions of the steel that contain chemical segregation caused by non-equilibrium solidi cation. Both pearlitic and cementite-free bainitic rails have been studied. The work is of generic value to the design of high-carbon microalloyed steels.
Introduction Rail steels rely primarily for their properties on wear and rolling-contact fatigue resistance [1–4]. The general characteristics of rail steels have been reviewed elsewhere [5]. It is, however, well known th