工程科学学报.第42卷，第11期：1481-1487.2020年11月 Chinese Journal of Engineering,Vol.42,No.11:1481-1487,November 2020 https://doi.org/10.13374/j.issn2095-9389.2019.11.21.004;http://cje.ustb.edu.cn 铈对工程机械用700MPa级高强钢焊接性能的影响 陆斌2)，陈芙蓉)区，刘伟建)，智建国2) 1)内蒙古工业大学材料科学与工程学院，呼和浩特0100512)包头钢铁（集团）有限责任公司，包头0140103)北京科技大学钢铁冶金新 技术国家重点实验室.北京100083 ☒通信作者，E-mail:cfr7075@vip.163.com 摘要针对工业生产700MPa级高强度调质态钢板，通过Gleeble3500热模拟机进行模拟焊接试验，利用光学显微镜、硬度 仪、场发射扫描电镜等设备对比研究了稀土C对高强钢焊接热影响区(HAZ)显微组织、晶粒度和力学性能的影响.研究结 果表明，焊接热输入为25kJcm和50kJcm时，无稀土钢焊接热影响区冲击功分别为84.8J和24.5J,Ce质量分数为 0.0018%的钢焊接热影响区冲击功分别为110.0J和112.0J.因此钢中加入适量C能够有效改善钢板焊接韧性.对比分析两 种实验钢焊接热影响区晶粒尺寸和显微组织可以看出，随着焊接热输入值增大，高强钢焊接热影响区显微组织均逐渐从马氏 体、下贝氏体转变为上贝氏体和粒状贝氏体组织，且奥氏体晶粒尺寸明显增大.但相同焊接热输入下，含C钢焊接热影响区 晶粒尺寸显著减小，组织更加细小，且脆性的上贝氏体组织减少，从而显著提高了7O0MP级高强钢的焊接性能. 关键词稀土：焊接热影响区；氧化物治金；700MPa级高强钢：冲击性能 分类号TG142.71 Effect of cerium on welding performance of 700 MPa high-strength steel used in construction machinery LU Bin2,CHEN Fu-rong,LIU Wei-jian,ZHI Jian-guo 1)School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot 010051,China 2)Baotou Iron and Steel Group Corp.,Baotou 014010,China 3)State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China Corresponding author,E-mail:cfr7075@vip.163.com ABSTRACT As the use of high-strength thick plates is increasing in marine engineering,bridge engineering,petroleum pipelines,and other fields,the required performance level of thick welded plates is also increasing.Oxide metallurgy technology,which is used to improve the toughness of heat-affected zones by controlling the formation and dispersion of high-melting-temperature oxide particles in steel,has attracted increasing attention by researchers in recent years.The effect of cerium on the welding performance of industrial quenched and tempered high-strength steel was investigated.Using a Gleeble 3500 thermal simulator,the coarse-grained heat-affected zones of high-strength steel were simulated with different cerium contents.The microstructures,austenite grains,and mechanical properties of the heat-affected zone were investigated by using optical microscopy,scanning electron microscopy equipped with energy dispersive spectrometry,and hardness testing.The results show that when the heat inputs are 25 kJ-cm and 50 kJ-cm,the impact energies of the heat-affected zone of Ce-undoped steel are 84.8 J and 24.5 J,respectively.When the mass fraction of Ce is 0.0018%,the impact energies of the heat-affected zone are 110.0 J and 112.0 J,respectively.The different degrees of toughness of the two experimental steels indicate that the appropriate content of rare earth element can effectively improve welding performance.By 收稿日期：2019-11-21 基金项目：国家重点研发计划资助项目(2016YFB0300604)铈对工程机械用 700 MPa 级高强钢焊接性能的影响 陆 斌1,2)，陈芙蓉1) 苣，刘伟建3)，智建国2) 1) 内蒙古工业大学材料科学与工程学院，呼和浩特 010051 2) 包头钢铁（集团）有限责任公司，包头 014010 3) 北京科技大学钢铁冶金新 技术国家重点实验室，北京 100083 苣通信作者，E-mail: cfr7075@vip.163.com 摘    要    针对工业生产 700 MPa 级高强度调质态钢板，通过 Gleeble3500 热模拟机进行模拟焊接试验，利用光学显微镜、硬度 仪、场发射扫描电镜等设备对比研究了稀土 Ce 对高强钢焊接热影响区（HAZ）显微组织、晶粒度和力学性能的影响. 研究结 果表明，焊接热输入为 25 kJ·cm−1 和 50 kJ·cm−1 时，无稀土钢焊接热影响区冲击功分别为 84.8 J 和 24.5 J，Ce 质量分数为 0.0018% 的钢焊接热影响区冲击功分别为 110.0 J 和 112.0 J，因此钢中加入适量 Ce 能够有效改善钢板焊接韧性. 对比分析两 种实验钢焊接热影响区晶粒尺寸和显微组织可以看出，随着焊接热输入值增大，高强钢焊接热影响区显微组织均逐渐从马氏 体、下贝氏体转变为上贝氏体和粒状贝氏体组织，且奥氏体晶粒尺寸明显增大. 但相同焊接热输入下，含 Ce 钢焊接热影响区 晶粒尺寸显著减小，组织更加细小，且脆性的上贝氏体组织减少，从而显著提高了 700 MPa 级高强钢的焊接性能. 关键词    稀土；焊接热影响区；氧化物冶金；700 MPa 级高强钢；冲击性能 分类号    TG142.71 Effect of cerium on welding performance of 700 MPa high-strength steel used in construction machinery LU Bin1,2) ，CHEN Fu-rong1) 苣 ，LIU Wei-jian3) ，ZHI Jian-guo2) 1) School of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051, China 2) Baotou Iron and Steel Group Corp., Baotou 014010, China 3) State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China 苣 Corresponding author, E-mail: cfr7075@vip.163.com ABSTRACT    As the use of high-strength thick plates is increasing in marine engineering, bridge engineering, petroleum pipelines, and other fields, the required performance level of thick welded plates is also increasing. Oxide metallurgy technology, which is used to improve the toughness of heat-affected zones by controlling the formation and dispersion of high-melting-temperature oxide particles in steel, has attracted increasing attention by researchers in recent years. The effect of cerium on the welding performance of industrial quenched and tempered high-strength steel was investigated. Using a Gleeble 3500 thermal simulator, the coarse-grained heat-affected zones of high-strength steel were simulated with different cerium contents. The microstructures, austenite grains, and mechanical properties of the heat-affected zone were investigated by using optical microscopy, scanning electron microscopy equipped with energy dispersive spectrometry, and hardness testing. The results show that when the heat inputs are 25 kJ·cm−1 and 50 kJ·cm−1, the impact energies of the heat-affected zone of Ce-undoped steel are 84.8 J and 24.5 J, respectively. When the mass fraction of Ce is 0.0018%, the impact energies of the heat-affected zone are 110.0 J and 112.0 J, respectively. The different degrees of toughness of the two experimental steels indicate that the appropriate content of rare earth element can effectively improve welding performance. By 收稿日期: 2019−11−21 基金项目: 国家重点研发计划资助项目（2016YFB0300604） 工程科学学报，第 42 卷，第 11 期：1481−1487，2020 年 11 月 Chinese Journal of Engineering, Vol. 42, No. 11: 1481−1487, November 2020 https://doi.org/10.13374/j.issn2095-9389.2019.11.21.004; http://cje.ustb.edu.cn