【摘要】 微合金高强度钢在油气运输领域的应用长达60余年,随着石油天然气工业的不断发展,对管线钢提出了高强韧、高可焊和抗氢致开裂等综合性能要求。首先回顾了微合金高强度钢的发展,探讨了Ti、Nb、V等微合金元素和Mn、Ni、Mo、Cu等合金元素对管线钢再结晶和相变的影响;在此基础上对微合金管线钢的加工工艺(控轧控冷(TMCP)、加速冷却(ACC)、超快冷(SFC)、在线加热配分(HOP)以及高温轧制(HTP))进行了详细介绍;并深入分析了控制轧制过程中奥氏体的再结晶行为及合金元素对奥氏体再结晶的影响机制,控制冷却过程中的相变行为及组织调控方法。最后,对微合金高强度钢的强韧化机理进行了分析,讨论了基于固溶强化、细晶强化、析出强化以及位错强化的强度计算方法,分析了晶粒尺寸、微观组织类型及取向相关性对冲击韧性的影响。可为新一代高强韧管线钢成分设计、加工工艺优化及组织调控提供理论与技术参考。更多还原

【Abstract】 The application of microalloyed high strength steel in the field of oil and gas transportation has lasted for more than 60 years.With the continuous development of the petroleum and natural gas industry, comprehensive performance requirements such as high toughness, high weldability, and hydrogen induced cracking resistance have been put forward for pipeline steels. Firstly, the development of microalloyed high strength steel is reviewed, and the effects of microalloying elements such as Ti, Nb, V, and alloying elements such as Mn, Ni, Mo, Cu on recrystallization and phase transformation of pipeline steels are explored. On this basis, a detailed introduction is given to the processing techniques of microalloyed pipeline steels, including thermo-mechanical control process( TMCP), accelerated cooling(ACC), super-fast cooling(SFC), heating on-line and partitioning(HOP), and high-temperature rolling(HTP). And in-depth analysis is conducted on the recrystallization behavior of austenite during the controlled rolling process and the influence mechanism of alloying elements on austenite recrystallization, as well as the phase transformation behavior and microstructure control methods during the controlled cooling process. Finally, the strengthening and toughening mechanism of microalloyed high strength steel is analyzed, and strength calculation methods based on solution strengthening, grain refinement strengthening, precipitation strengthening and dislocation strengthening are discussed. The effects of grain size, microstructure type and orientation correlation on impact toughness are analyzed. It can provide theoretical and technical references for the composition design, processing technology optimization, and microstructure control of the new generation of high strength and toughness pipeline steels.更多还原