焊管2026，Vol.49Issue(4)：23-31,9.DOI:10.19291/j.cnki.1001-3938.2026.04.003
12Mn管线钢夹杂物钙处理的热力学分析和试验研究
Thermodynamic and Experimental Studies on Effect of Calcium Treatment on Inclusions of 12Mn Pipeline Steel
摘要
Abstract
This study focuses on 12Mn pipeline steel with high manganese content(1.15%～1.35%)serving in deep-sea high-pressure environments,which suffers from an 8%～12%scrap rate due to inclusion-induced cracking.By adopting a combined technical approachcomprising microscale characterization(SEM/ASPEX),submicroscale analysis(TEM),and thermodynamic calculation,systematic calcium treatment process experiments were conducted to investigate the inclusion control mechanism and its correlation with microcracks.The results show that the primary inducement of microcracks in 12Mn pipeline steel is irregular Al₂O₃ inclusions(covering both microscale and submicroscale).Specifically,the proportion of Al₂O₃ in the crack region(68%)is three times that in the normal region(23%);the density of inclusions larger than 5 µm in the crack region(45.2 particles/mm²)is 3.6 timesthat in the normal region(12.5 particles/mm²);and the probability of stress concentration induced by irregular Al₂O₃ reaches 92%.The optimized exclusive calcium treatment parameters for 12Mn steel can increase the calcium recovery rate to 28%and promote the transformation of Al ₂ O ₃ into low-melting calcium aluminate.After treatment with this process,the inclusion circularity increases from 0.32 to 0.78,the stress concentration probability decreases to less than 5%,and the crack scrap rate of 12Mn finished pipes drops from 12%to 3%,without excessive formation of CaS(CaS proportion<8%).This calcium-based treatment technology for 12Mn steel provides key theoretical support and actionable industrial guidance for the engineering design of inclusions and the optimization of mass production processes for high-Mn pipeline steels.关键词
12Mn管线钢/钙处理/热力学分析/夹杂物/ASPEX检测Key words
12Mn pipeline steel/calcium treatment/thermodynamic analysis/inclusions/ASPEX detection分类
矿业与冶金引用本文复制引用
王旭,赵立前,陈祥,霍玉香,董磊..12Mn管线钢夹杂物钙处理的热力学分析和试验研究[J].焊管,2026,49(4):23-31,9.基金项目
内蒙古自治区科技重大专项"中低压纯氢与掺氢燃气管道输送及其应用关键技术研发"(项目编号2023YFJM0004、2021SZD0082) （项目编号2023YFJM0004、2021SZD0082）
中国石油管道工程有限公司项目资助"纯氢管线钢、环焊缝等相关性能氢损伤影响分析及评价研究"(项目编号2024-22). （项目编号2024-22）
