摘要
灰斑是钢轨闪光焊接头中常见的缺陷,对钢轨焊接接头质量有直接的影响.本文通过研究挤出瘤中的夹杂物组织及其形态,并在钢轨闪光焊完成预热烧化后终止焊接作业,取样分析,以探究灰斑的形成原因.结果表明:焊接过程中熔融金属与氧发生反应,各种成分通过扩散作用不断聚集,最终在焊缝局部区域形成硅酸盐夹杂物.受焊接工艺影响及夹杂物流动性差异,顶锻阶段少部分夹杂物未被挤出,从而在焊缝内部形成灰斑.
Gray-spot is a common defect in rail flash welded joint,which has a direct impact on the quality of rail welding joint.In this paper,the microstructure and morphology of inclusions in the extrusion tumor were studied.After preheating and flashing of the rail flash welding,the welding operation was terminated and sampling analysis was conducted to explore the causes of the flat spots.The results show that,the molten metal reacts with oxygen,and various components gather continuously through diffusion,finally forming silicate inclusions in the local area of the welding joint during the welding process.Due to the influence of welding technology and the difference of inclusion fluidity,a few inclusions were not extruded in the upsetting stage,which resulted in the formation of gray-spots in the weld.
作者
高伟
GAO Wei(Lanzhou Works Mechanical Section,China Railway Lanzhou Bureau Co.Ltd.,Lanzhou 730050,China)
出处
《铁道建筑》
北大核心
2020年第5期119-122,共4页
Railway Engineering
关键词
钢轨
闪光焊
灰斑
形成机制
硅酸盐夹杂物
试验研究
rail
flash welding
gray-spots
formation mechanism
silicate inclusion
experimental study
