低温高强韧性管线钢组织细化工艺的研究和应用  

Research and Application of Microstructure Refining Technology of Low-temperature High-strength and High-toughness Pipeline Steel

作　　者：聂文金[1] 林涛铸 郭志龙 曲锦波 尚成嘉[3] 张晓兵[1] NIE Wenjin;LIN Taozhu;GUO Zhilong;QU Jinbo;SHANG Chengjia;ZHANG Xiaobing(Jiangsu Shagang Group Co., Ltd., Zhangjiagang Jiangsu 215625, China;Institute of Research of Iron and Steel, Shasteel, Zhangjiagang Jiangsu 215625, China;School of Material Science and Technology, University of Science and Technology Beijing, Beijing 100083, China)

机构地区：[1]江苏沙钢集团有限公司,江苏张家港215625 [2]江苏省(沙钢)钢铁研究院,江苏张家港215625 [3]北京科技大学材料科学与工程学院,北京100083

出　　处：《上海金属》2021年第3期7-12,共6页Shanghai Metals

基　　金：国家重点研发计划(No.2017YFB0304900)。

摘　　要：采用Gleeble-3800热/力模拟试验机研究了成分(质量分数,下同)为0.03%C-1.70%Mn-0.10%Nb的管线钢压缩变形奥氏体的再结晶行为及连续冷却相变过程。结果表明:在950℃以5道次、每道次20%的变形量、1 s^(-1)的变形速率和12 s的道次间隔时间压缩变形的试验钢,累计变形量达到40%时发生再结晶,而在850℃以相同工艺压缩变形至相同程度的钢未发生再结晶,继续变形则每道次均发生动态再结晶,总体上应力随应变的增大而增大;在950和850℃压缩变形60%后以45℃/s速率冷却至室温,850℃变形的钢中≥15°和≥45°的大角晶界密度比950℃变形的钢分别提高了1.6%和3.2%。工业冶炼的成分为0.06%C-1.70%Mn-0.065%Nb、用于外径1422 mm、壁厚30.8 mm管线的X80M钢,从非再结晶区850℃始轧随后以大于13℃/s的速率冷却后,具有良好的强韧性。Recrystallization behavior and continuous cooling transformation of compression-deformed austenite in the pipeline steel whose composition(mass fraction,the same below)was 0.03%C-1.70%Mn-0.10%Nb were investigated by a Gleeble-3800 thermo-mechanical simulator.From the experimental investigation it was seen that the investigated steel which was compression deformed to 40%at 5-pass deformation,20%deformation per pass,strain rate of 1 s^(-1) and interval time of 12 s at 950℃exhibited recrystallization,but no recrystallization at 850℃,and as the deformation proceeded,dynamic recrystallization occurred in each pass,generally,the stress increased with the strain.Densities of grain boundary with angles as large as≥15°and≥45°in the steel compression deformed at 850℃to 60%then cooled at a rate of 45℃/s to room temperature were respectively 1.6%and 3.2%larger than those of the steel compression deformed at 950℃to the same degree then cooled by the same procedure.The X80M steel whose composition was 0.06%C-1.70%Mn-0.065%Nb used for pipeline 1422 mm in outer diameter by 30.8 mm wall thickness offered excellent both strength and toughness after rolling from 850℃in the non-recrystallization region followed by cooling at above 13℃/s.

关 键 词：X80管线钢 再结晶 相变 细化 

分 类 号：TG142.11[一般工业技术—材料科学与工程]