摘要
实现传统钢铁材料性能的全面升级符合社会可持续发展战略,组织超细化是同时提高钢铁材料强度和韧性的最佳强化机制。大量研究成果表明,通过不同的晶粒细化工艺可使钢铁材料组织细化到微米级、亚微米级和纳米级,使得传统钢铁材料的综合力学性能得到大幅度提高。但目前困扰超细晶粒钢的焊接技术尚未得到彻底解决。现阶段易于工业化晶粒超细化处理工艺所制备的超细晶粒钢,其焊接问题主要表现为焊接热影响区(HAZ)存在不同程度的脆化和局部软化现象,严重影响了焊接接头与母材性能的匹配。基于氧化物夹杂诱导形核的晶内针状铁素体组织强度高、韧性好,具有很强的自身细化能力,通过氧化物冶金技术获得具有大量有益微夹杂物的超细晶粒钢有望解决其焊接性问题。深入研究钢材基体中超细夹杂物形成与作用机理和焊接HAZ晶内针状铁素体的形成规律及影响因素,制备焊接性能良好的超细晶粒钢是新一代超级钢材料研究的重要发展方向。
It meets the requirement of sustainable development of the society to upgrade roundly the performance of the traditional iron and steel materials, and microstructure ultra-fining treatment is proved to be the optimum way that can improve both the strength and the toughness. Lots of research achievements show that the microstructure of the iron and steel materials can be refined to micro-scale, submicro-scale and nano-scale through various grain fining technologies, as a result, their comprehensive mechanical properties are improved remarkably. However, the welding technique of the ultra-fine grained steels hasn＇t been solved thoroughly as yet. As for those steels produced by the ultra-fining treatments which are easy to industrialize, the main welding problems are characterized by embrittlement in varying degrees and local softening in welded heat affected zones （ HAZ）, which affect severely the properties matching between the welded joint and the base metal. Intragranular acicular ferrite microstructures, which are nucleated around oxide inclusions, have high strength and good toughness, and possess strong grain-fining ability by themselves. It＇ s hopeful to solve the weldability problems of the ultra-fine grained steels with a large number of useful micro-inclusions obtained by oxides metallurgy technology. So, to make a thorough study of the formation and action mechanisms of the micro-inclusions in base metal and the formation law and influencing factors of the intragranular acicular ferrites in welded HAZ, and then to produce ultra-fine grained steels with good weldability become an important developmental direction for the new generation super-steel study.
出处
《中国石油大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2007年第2期155-162,共8页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家自然科学基金资助项目(59971031)
国家重点自然科学基金(50334050)
上海宝钢集团公司联合资助项目
关键词
超细晶粒钢
组织超细化
焊接技术
氧化物冶金
超细夹杂物
针状铁素体
ultra-fine grained steel
microstructure ultra-fining treatment
welding technique
oxides metallurgy
micro-inclusion
acicular ferrite
