铝锂合金的真空电子束焊接工艺及其接头组织与性能  

Electron beam welding technology and microstructure and mechanical properties of welded joints for 2090 Al-Li alloy

作　　者：俞旷[1] 王少刚[1] 陈忱[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,江苏南京210016

出　　处：《电焊机》2011年第2期70-75,共6页Electric Welding Machine

摘　　要：采用真空电子束焊工艺焊接2090铝锂合金,并对获得接头进行拉伸强度、显微硬度等力学性能测试,对接头的金相组织、拉伸断口进行观察分析。结果表明,在电子束流为8 mA,采用圆形扫描方式,焊接速度为1 000 mm/min的工艺条件下,获得的接头的力学性能最佳。接头微观分析显示,焊缝金属为细小等轴晶组织,在晶内均匀分布有数量较多的强化相。进一步的接头焊缝XRD分析显示,焊缝金属基体为α-Al,并含有δ′、β′、T1、θ′等强化相。拉伸断口扫描观察表明,接头断口表面分布有大量细小的韧窝,呈明显韧性断裂特征。The mechanical properties and microstructure of 2090 Al-Li alloy joints welded by electron beam with different parameters are investigated in this paper.The tensile strength and microhardness of the welded joint are tested,and the joint microstructure and fracture, are analyzed respectively.Results show that joint with excellent mechanical properties can be obtained under the welding parameters （1=8 mA,v=1 000 mm/min,circular scanning）.The joint microsturcture analysis demonstrates that the weldment mainly consists of fine equiaxed grains,and also great precipitation of strengthening phases uniformly distribute in the inner of grains.The XRD analysis of weld metal indicates that there are dominant a -Al phase in the matrix metal of joint,and the other strengthening phases such as ,δ ＇ , β ＇ ,T1, θ＇ ,ete.The scanning analysis of joint shows that there are a large number of small dimples on the fracture surface, and the joint obviously presents the characteristic of ductile fracture.

关 键 词：2090铝锂合金 电子束焊 力学性能 微观分析 

分 类 号：TG456.3[金属学及工艺—焊接]