耐低温合金钢及其焊接接头组织性能研究进展

Research progress on low temperature resistant alloy steel and its microstructure and properties of welded joint

耐低温合金钢因在低温下具有足够的强度、优异的韧性和抗脆性断裂能力,在低温服役条件下被广泛使用。目前,国内外对低温用钢的温度界限还没有统一的规定,如何提高低温钢的低温韧性和焊接接头性能仍是比较棘手的问题。文中综述了按相组成划分的双相低温钢的研究现状,着重介绍了成分设计、组织演变规律和组织与性能调控等;归纳总结了影响耐低温钢焊接接头组织性能的主要因素,包括合金元素、热处理工艺、焊接工艺等。合理的成分设计、优化制备工艺和了解失效机制是实现耐低温合金钢工程化应用的基础;微合金化、控轧控冷(TMCP)和增材制造(AM)技术是未来开发高强高韧低温结构钢的重要手段;将计算科学引入合金设计和损伤机制的研究,以实现整个制备过程的可操控性,是未来研究的重点。

Low temperature resistant alloy steel is widely used in cryogenic service conditions due to its sufficient strength at low temperature,excellent toughness and brittle fracture resistance.Now,there is no unified temperature limit for low temperature alloy steel at domestic and abroad,and how to improve the cryogenic toughness and welded joint properties of the steel is still a difficult problem.The current research on dual-phase cryogenic steel classified by phase compositions was reviewed,and the composition design,tissue evolution laws and tissue and property regulation was emphatically introduced.The main factors affecting the microstructure and properties of welded joints of low temperature resistant steels were summarized,including alloying elements,heat treatment processes,welding processes,etc.Reasonable composition design,optimization of the preparation process and understanding of the failure mechanism was the basis for the engineering application of low temperature resistant alloy steel.Microalloying,Thermal Mechanical Control Processing(TMCP)and Additive Manufacturing(AM)technologies are important tools for the future development of high-strength,high-toughness and low-temperature structural steels.The introduction of computational science into the study of alloy design and damage mechanisms to achieve the manipulability of the entire preparation process is the focus of future research.