{"title":"Microstructure and strengthening mechanisms of heavy gauge pipeline steel processed by ultra-fast cooling (UFC) versus laminar cooling (LC)","authors":"Haijian Xu, Chunfei Han, Yan Zang, Wenyue Liu, Weijuan Li, X. Sha","doi":"10.1080/03019233.2023.2216093","DOIUrl":null,"url":null,"abstract":"ABSTRACT In this study, a novel thermo-mechanical controlled processing (TMCP) schedule, based on ultrafast cooling (UFC), was used to fabricate heavy gauge X80 pipeline steels for solving the low qualification drop-weight-tear test (DWTT) properties. The microstructures of the X80 pipeline steels were all composed of quasi-polygonal, acicular ferrite (AF), and granular bainite (GB) produced by Laminar Cooling (LC) and UFC. The grain sizes were finer and the average length of HAG was higher produced by UFC. The main strengthening mechanisms in LC-process steel were grain strengthening and precipitation strengthening, and dislocation strengthening. However, the main strengthening contribution in UFC-process was related to grain strengthening and dislocation strengthening. The decrease in strength induced by reducing Nb, Mo, and Cr contents in UFC steel was compensated by increasing the contribution of grain strengthening. In conclusion, the low-cost X80 pipeline steels can be produced by UFC without degradation of strength and toughness.","PeriodicalId":14753,"journal":{"name":"Ironmaking & Steelmaking","volume":"50 1","pages":"1385 - 1393"},"PeriodicalIF":1.7000,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ironmaking & Steelmaking","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1080/03019233.2023.2216093","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"METALLURGY & METALLURGICAL ENGINEERING","Score":null,"Total":0}
引用次数: 0
Abstract
ABSTRACT In this study, a novel thermo-mechanical controlled processing (TMCP) schedule, based on ultrafast cooling (UFC), was used to fabricate heavy gauge X80 pipeline steels for solving the low qualification drop-weight-tear test (DWTT) properties. The microstructures of the X80 pipeline steels were all composed of quasi-polygonal, acicular ferrite (AF), and granular bainite (GB) produced by Laminar Cooling (LC) and UFC. The grain sizes were finer and the average length of HAG was higher produced by UFC. The main strengthening mechanisms in LC-process steel were grain strengthening and precipitation strengthening, and dislocation strengthening. However, the main strengthening contribution in UFC-process was related to grain strengthening and dislocation strengthening. The decrease in strength induced by reducing Nb, Mo, and Cr contents in UFC steel was compensated by increasing the contribution of grain strengthening. In conclusion, the low-cost X80 pipeline steels can be produced by UFC without degradation of strength and toughness.
期刊介绍:
Ironmaking & Steelmaking: Processes, Products and Applications monitors international technological advances in the industry with a strong element of engineering and product related material. First class refereed papers from the international iron and steel community cover all stages of the process, from ironmaking and its attendant technologies, through casting and steelmaking, to rolling, forming and delivery of the product, including monitoring, quality assurance and environmental issues. The journal also carries research profiles, features on technological and industry developments and expert reviews on major conferences.