摘要
Ti-Mg脱氧工艺可有效提高钢材的大线能量焊接性能,实焊条件下该类钢的组织特征及影响机理有待进一步研究。本文对比研究了Ti-Mg脱氧钢和普通工艺钢,开展了气电立焊大线能量焊接试验,检测了焊接接头组织与性能,采用电解萃取的方法提取钢中夹杂物,并进行扫描电镜表征,分析了脱氧工艺对焊接组织和性能的影响机理。结果表明,Ti-Mg复合脱氧工艺下钢中主要形成细小弥散的球状Ti-Mg-O型夹杂物,改善了夹杂物形态,减轻了对钢材基体性能的不利影响。大线能量焊接过程中,微细氧化物钉扎细化粗晶热影响区的奥氏体晶粒,消除仿晶铁素体和侧板条结构,促进针状铁素体组织转变,显著提高焊接接头冲击韧性。
Ti-Mg deoxidation process can effectively improve the large heat input welding performance of steels.The microstructure characteristics and influence mechanism of the steel under actual welding conditions need further study.In this paper,Ti-Mg deoxidized steel and ordinary steel were compared and studied,and the large heat input electo-gas vertical welding experiment was carried out.The microstructure and properties of the welded joints were tested.The inclusions in steel were extracted by the method of electrolytic extraction and characterized by scanning electron microscope.The influence mechanism of deoxidation process on the welding microstructure and toughness was analyzed.The results show that fine and dispersed spherical Ti-Mg-O type inclusions are mainly formed in the steel under Ti-Mg composite deoxidization process,which improves the inclusion morphology and reduce the adverse effect on the properties of the steel matrix.In large heat input welding process,the fine oxide particles pin austenite grains in the coarse-grained heat affected zone and eliminate allotriomorphic ferrite and side plate structure,and promote the formation of acicular ferrite,and the impact toughness of the welded joint is significantly improved.
作者
张欣瑶
胡珂
王天舜
李志
郝俊杰
王超
ZHANG Xinyao;HU Ke;WANG Tianshun;LI Zhi;HAO Junjie;WANG Chao(School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China)
出处
《热加工工艺》
北大核心
2024年第19期39-43,共5页
Hot Working Technology
基金
国家自然科学基金资助项目(U21A20116)。
关键词
大线能量焊接用钢
Ti-Mg脱氧
针状铁素体
冲击韧性
气电立焊
large heat input welding steel
Ti-Mg deoxidation
acicular ferrite
impact toughness
electo-gas vertical welding
