终冷温度对厚规格X80组织和DWTT的影响  

Effect of final cooling temperature on the microstructure and DWTT of thick X80 linepipe steel strip

作　　者：叶晓瑜 任守斌[3] 李拔 贾书君[4] 张开华[2] 黄贞益[1] Ye Xiaoyu;Ren Shoubin;Li Ba;Jia Shujun;Zhang Kaihua;Huang Zhenyi(School of Metallurgical Engineering,Anhui University of Technology,Ma,anshan 243002,Anhui,China;Pangang Group Research Institute Co.,Ltd.,State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization,Panzhihua 617000,Sichuan,China;Xichang Steel&Vanadium Co.,Ltd.,Pangang Group,Xichang 615000,Sichuan,China;Engineering Steel Research Institute,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243002 [2]攀钢集团研究院有限公司,钒钛资源综合利用国家重点实验室,四川攀枝花617000 [3]攀钢集团西昌钢钒有限公司,四川西昌615000 [4]钢铁研究总院工程用钢所,北京100081

出　　处：《钢铁钒钛》2022年第4期167-172,共6页Iron Steel Vanadium Titanium

摘　　要：通过显微组织和落锤试样的断裂路径表征,研究了不同终冷温度对21.4 mm厚X80组织和落锤性能的影响,分析了不同组织对裂纹扩展路径的影响。试验结果表明,当终冷温度为480℃时,其组织为粒状贝氏体+细小的准多边形铁素体,当终冷温度提高到510℃时,在心部出现大尺寸的多边形铁素体,随着终冷温度提高,大尺寸的多边形铁素体含量增加。当终冷温度从480℃提高到550℃时,整个断面的组织由全针状铁素体组织向边部针状铁素体组织+心部大尺寸多边形铁素体组织转变,心部的大尺寸多边形铁素体组织不能有效阻止裂纹的扩展,落锤剪切面积从100%降低到72%。The effects of different final cooling temperatures on the microstructure and drop weight properties of 21.4 mm thick X80 linepipe steel strip were studied,and the effect of different microstructure on crack propagation path was discussed.When the final cooling temperature is 480℃,the microstructure of the resulted steel strip is composed of granular bainite+fine quasi-polygonal ferrite.When the final cooling temperature is increased to 510℃,large-size polygonal ferrite appears in the core of strip sample.As the final cooling temperature further increases,the volume fraction of large-size polygonal ferrite increases.When the final cooling temperature is increased from 480℃to 550℃,the microrstructure across cross section transforms from fully acicular ferrite to acicular ferrite in the edge+large-size polygonal ferrite in the core.Since the large-size polygonal ferrite in the core cannot restrain crack propagation effectively,the drop weight shear area of tested steel decreases from 100%to 72%with cooling temperature increasing from 480℃to 550℃.

关 键 词：X80管线钢 终冷温度 铁素体 落锤撕裂试验 裂纹 

分 类 号：TF76[冶金工程—钢铁冶金] TG115[金属学及工艺—物理冶金]