东北大学学报:自然科学版 ›› 2018, Vol. 39 ›› Issue (8): 1123-1126.DOI: 10.12068/j.issn.1005-3026.2018.08.012

• 材料与冶金 • 上一篇    下一篇

高韧性420MPa级桥梁钢开发及强化机制分析

高彩茹1, 刘宝喜2, 潘欢1, 高秀华1   

  1. (1. 东北大学 轧制技术及连轧自动化国家重点实验室, 辽宁 沈阳110819; 2. 唐山钢铁集团有限责任公司 技术中心, 河北 唐山063002)
  • 收稿日期:2017-04-12 修回日期:2017-04-12 出版日期:2018-08-15 发布日期:2018-09-12
  • 通讯作者: 高彩茹
  • 作者简介:高彩茹(1965-),女,内蒙古赤峰人,东北大学副教授,博士.冯明杰(1971-), 男, 河南禹州人, 东北大学副教授; 王恩刚(1962-), 男, 辽宁沈阳人, 东北大学教授,博士生导师.
  • 基金资助:
    国家高技术研究发展计划项目(2015AA03A501).国家自然科学基金资助项目(51171041).

Development and Strengthening Mechanism of 420MPa Grade Bridge Steel with High Toughness

GAO Cai-ru1, LIU Bao-xi2, PAN Huan1, GAO Xiu-hua1   

  1. 1.State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China; 2. Technology Center, Tangshan Iron and Steel Group,Tangshan 063002, China.
  • Received:2017-04-12 Revised:2017-04-12 Online:2018-08-15 Published:2018-09-12
  • Contact: GAO Cai-ru
  • About author:-
  • Supported by:
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摘要: 通过优化合金成分、改进控轧控冷工艺等手段,成功开发出屈服强度在480~530MPa,抗拉强度在560~630MPa,延伸率在21%~25%,-20℃冲击功全部在200J以上的Q420桥梁钢.对透射电镜下的析出相及金相显微组织中的晶粒尺寸进行相关统计计算,得到各类强化贡献量数值,并对Q420桥梁钢的强化机制进行了分析.分析结果表明:在新开发的Q420桥梁钢中析出强化贡献量占全部强度的10%以下,而固溶强化量及细晶强化量分别占全部强度的54%及36%,因此确认420MPa级桥梁钢的强化机制以固溶强化、细晶强化为主.

关键词: 控轧控冷, 高韧性, 420MPa级桥梁钢, 强化机制, 强度计算

Abstract: The Q420 bridge steel with yield strength of 480~ 530MPa, tensile strength of 560~ 630MPa, elongation of 21 %~ 25% and impact strength of more than 200J at-20℃was developed by optimization of alloy composition and improvement of control rolling and control cooling process. The amount of various types of strengthening contribution was obtained through analyzing the amount of precipitation by transmission electron microscopy and the grain size of metallographic microstructure. Then the strengthening mechanism of Q420 bridge steel was studied. The results showed that the contribution of precipitation strengthening accounts for less than 10% of the total strength for Q420 bridge steel, and the contribution of solid solution strengthening and fine grain strengthening are 54% and 36%,respectively.It is confirmed that solid solution strengthening and fine grain strengthening are dominated in 420MPa grade steel.

Key words: control rolling and control cooling, high toughness, 420MPa grade bridge steel, strengthening mechanism, strength calculation

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