钛合金蒙皮骨架结构激光焊接工艺与组织研究  

Research on Formation and Microstructure Characteristic of Laser Welded Frame-covering Structures of TC4 Titanium Alloy

作　　者：赵颖[1] 龙丹 赵勇[1] 黄坚[1] 

机构地区：[1]上海交通大学上海市激光制造与材料表面改性重点实验室,上海200240 [2]广州起重机械有限公司,广州510897

出　　处：《热加工工艺》2012年第7期149-152,共4页Hot Working Technology

摘　　要：针对钛合金蒙皮骨架结构,研究了不同激光焊接工艺参数对其焊缝成形的影响,观察并分析了焊缝的微观组织形貌。结果表明:焊缝熔深、熔宽随着激光功率的升高和焊接速度的降低逐渐增加;骨架的宽度、厚度以及蒙皮与骨架间的间隙量对熔深、熔宽的影响不大,间隙量增大使焊缝表面咬边、凹陷明显;焊缝组织为针状马氏体α'组成的网篮组织,热影响区中存在少量细小马氏体组织,且呈梯度分布。由于马氏体的界面增强效应,焊缝横向显微硬度沿焊缝中心向母材逐渐降低;蒙皮上焊缝的显微硬度值略高于骨架上焊缝硬度值。The forrnatio n and microstructure of TC4 laser welding joints with different welding parameters were studied. The results show that both weld penetration and width increase with the laser power increasing and welding speed decreasing. The width and thickness of the skeleton, and the gap between covering and skeleton have little influence on variation of weld penetration and width. Increase in the gap makes bite side and hollow obvious. The microstructure of the FA consists of mainly a＇ phase, the HAZ is a mixture of primary ct and a＇. Covering has higher microhardness in the FZ and HAZ than the skeleton has. Along the weld center to the base metal, weld transverse microhardness graduaUy reduces, dueing to the interface enhancement effect of martensites.

关 键 词：钛合金 激光焊接 焊缝成形 组织 

分 类 号：TG456.7[金属学及工艺—焊接]