X80 管线钢的物理冶金原理研究及其应用管线钢的物理冶金原理研究及其应用 尚成嘉1，刘清友2，付俊岩3 1. 北京科技大学-CITIC-CBMMM 铌钢联合实验室，北京 100083 2. 北京钢研院-CITIC-CBMM 合金钢与低合金钢联合实验室,北京，100086 3. 中信金属公司，中信微合金化技术中心，北京 100004 摘要：摘要：高等级管线用钢的发展与冶金技术的进步和石油、天然气管线工程的发展密切相连的，她的发展历程和成就也是中国钢铁工业和石油天然气管道工业的发展历程和成就的体现当前，中国正在实施建设的“西气东输二线”天然气管线，工作压力从以往不到 6MPa 发展到目前的 12MPa，口径从以往不到 660 mm，发展到现在的壁厚大于 18.4mm 的 1219 mm 直径的大口径高压输送[1]她是当今世界上在长度最长（约 8000Km）管道上采用高等级 X80 管线钢的高技术工程随着我国能源结构调整和环保需求，对天然气的需求不断增加，我国高等级管线钢的技术必将继续发展，为 X80 及 X100- X120 更高等级管线钢的应用提供历史机遇 随着现代冶金技术的不断进步，管线钢的生产工艺在炼钢上采用了超低碳、超低硫、夹杂物形态控制的纯净钢冶炼技术，在热轧方面采用热机械处理 TMCP 技术，通过合理的成分设计和工艺控制得到具有最佳强韧性的组织结构，以满足石油天然气管道建设用高等级管线钢所需的高强度、高韧性和良好焊接性等综合性能。
近年来，我国在 X80 管线钢的低碳- 高铌合金设计- 工艺控制显微组织结构强韧化机理的研究中，不仅发展了国外原有的HTP 技术，并在确认低碳高铌合金设计的合理性的前提下，对在平板轧机和热连轧机组生产厚规格板材（≥18.4mm）如何控制显微组织及其强韧化的 TMCP 工艺技术进行了深入的研究，优化了 TMCP 技术，在太钢、首钢、鞍钢、沙钢等钢厂进行了生产实践，成功地协助钢厂解决了技术难题，不仅保证了西气东输二线建设合格产品的及时供应，且全面提升了我国管线钢研究和生产技术水平 Physical Metallurgy Phenomenon Research on X80 Pipeline Steel and its Application Chengjia Shang1, Qingyou Liu2, Junyan Fu3 1 University of Science and Technology Beijing, Beijing, 100083, China 2 China Iron and Steel Research Institute, Beijing, 100081, China 3 CITIC- CBMM Microalloying Technology Center, Beijing, 100004 , China Abstract: High Mn- high Nb approach X80 pipeline is being applied in Chinese East to West Gas Pipeline Project. The diameter of both spiral and UOE/JCOE pipe is 1219mm with thickness of 18.4mm and 22mm, respectively[1]. For meeting the requirement of high performance, various metallurgical phenomenon of high Mn- high Nb pipeline steel need to be concerned during contrl rolling and accelerated cooling. No matter which rolling process is employed, grain refinement and strain accumulation still are the key for obtain good properties, which are influenced by recovery of dislocation, static and dynamic recrystallization of austenite grain and precipitates. However, how to refine austenite grain and accumulate strain effectively isn’t understood clearly in the case of high Mn- high Nb approach. Many literatures[2] have mentioned that higher Nb content can increase static recrystallization stop temperature (Tnr), finish rolling process can be started at higher temperature as non- recrystallization temperature (Tn5) would be increased by Nb content increasing. But for higher Mn- Nb system, precipitation of Nb(C,N) is delayed compared with less Mn- Nb system[3] during relaxing of deformed austenite at high temperature, moreover, dragging force (compared with precipitates) would not strong enough to retard recovery and recrystallization[3]. Therefore, non- recrystalization temperature range of high Mn- high Nb system should be reconsidered. Less precipitates result in stronger dragging force because of more niobium in solution, thus it is possible to an existence of new temperature region based on the new characteristic of high Mn high Nb, in which new grain nucleation occurs as usual, but growth rate is very slow because of much stronger dragging force. The other important thing during hot rolling is strain accumulation or high Sv. The recovery between passes would be retarded and accumulated strain rate is higher for higher Nb steel as drag effect of soluble Nb, and it would increase possibility of DRX and meta- dynamic recrystalliation (MDRX), especially in finish rolling of hot strip mill. In industry, actual static and dynamic recrystallizaiton behaviors in different conditions should be considered for HSM and PM, which have different metallurgical characteristics, respectively. In addition, the accelerate cooling will influnece the transformation phases deeply. The high Mn- high Nb content without Mo and /or with Mo will have different transformation characteristic. Therefore, the control cooling process should be optimized for obtain fine bainitic ferrite and dispersive M/A constitunt. The key accelerate cooling parameters, such as cooling rate, start and finish temperature should be determined for strengthening and toughening the steel. The physical metallurgy principles during TMCP of X80 pipeline steel have been revealed and applied for X80 pipeline steel manufacture in several hot strip plate mill rolling lines. The high performance pipeline steel has been pruduced and the properties can meet the strick specification. 高等级管线用钢的发展与冶金技术的进步和石 油、天然气管线工程的发展密切相连的，她的发展历 程和成就也是中国钢铁工业和石油天然气管道工业 的发展历程和成就的体现。
当前，中国正在实施建设 的“西气东输二线”天然气管线，工作压力从以往不到 6MPa 发展到目前的 12MPa，口径从以往不到 660 mm，发展到现在的壁厚大于 18.4mm的 1219 mm 直 径的大口径高压输送[1] 她是当今世界上在长度最长 （约 8000Km） 管道上采用高等级 X80 管线钢的高技 术工程随着我国能源结构调整和环保需求，对天然 气的需求不断增加， 我国高等级管线钢的技术必将继 续发展，为 X80 及 X100- X120 更高等级管线钢的应 用提供历史机遇 随着现代冶金技术的不断进步， 管线钢的生产工 艺在炼钢上采用了超低碳、超低硫、夹杂物形态控制 的纯净钢冶炼技术，在热轧方面采用热机械处理 TMCP 技术， 通过合理的成分设计和工艺控制得到具 有最佳强韧性的组织结构， 以满足石油天然气管道建 设用高等级管线钢所需的高强度、 高韧性和良好焊接 性等综合性能 近年来，我国在 X80 管线钢的低碳- 高铌合金设计- 工 艺控制显微组织结构强韧化机理的研究中， 不仅发展 了国外原有的 HTP 技术，并在确认低碳高铌合金设 计的合理性的前提下， 对在平板轧机和热连轧机组生 产厚规格板材（≥18.4mm）如何控制显微组织及其 强韧化的 TMCP 工艺技术进行了深入的研究， 优化了 TMCP 技术，在太钢、首钢、鞍钢、沙钢等钢厂进行 了生产实践，成功地协助钢厂解决了技术难题，不仅 保证了西气东输二线建设合格产。