摘要
成功采用激光焊/超塑成形组合工艺制作四层板结构件,分析了超塑性变形前后激光焊缝显微组织变化及其原因,并与扩散焊/超塑成形组合工艺制作的四层板结构件组织结构进行了对比。结果表明:激光焊缝组织发生α′→α+β转变,并在应力应变作用下细长针状组织转变成粗短的层状组织,使焊缝具有承受超塑性变形的能力,同时有利于降低接头的脆性和硬度,提高零件的使用寿命;与扩散焊/超塑成形组合工艺相比,激光焊/超塑成形组合工艺大大降低了零件加工过程的高温持续时间,减小了工件的晶粒尺寸。
Laser lap welding/superplastic deformation (LBW/SPF) process was successfully used to manufacture four-sheet structure.Microstructures of laser lap welded joint before and after superplastic deformation were observed and analyzed,and the grain size of the base metal was compared with that of four-sheet structure made by diffusion bonding/superplastic deformation (DB/SPF).The results showed that the microstructure of weld bead can be transformed from martensite α' phase to α+β phase,and the acicular structure was changed into the lamellar structure,which improves its affordability to deformation.Compared with DB/SPF,LBW/SPF reduced the duration of parts at high temperature and restrained the grain growth.
出处
《焊接》
北大核心
2009年第8期20-22,共3页
Welding & Joining
关键词
激光叠焊
超塑成形
四层板结构件
laser lap welding
superplastic deformation
four-sheet structure
