摘要
采用摆动激光焊对TC4钛合金焊接接头进行重熔,研究摆动频率对TC4钛合金焊接接头气孔、组织及力学性能的影响。结果表明,重熔摆动激光焊可有效消除TC4钛合金焊接接头中存在的气孔缺陷;随着摆动频率的增加,气孔的消除效果增强,且大气孔的消除效果变得更加明显。重熔摆动激光焊接头的焊缝组织为针状的α'马氏体和部分α相,热影响区组织由初生α相、针状α'马氏体及β相组成。随着摆动频率的增加,激光对熔池的搅拌作用增强,焊缝晶粒破碎逐渐细化,而热影响区晶粒生长变得更加有利,导致晶粒逐渐粗大。摆动频率的增加使焊接接头组织发生变化,进而导致焊接接头性能发生变化。随着摆动频率的增大,TC4重熔焊接接头的焊缝硬度上升,热影响区硬度逐渐下降,且焊接接头的拉伸性能呈现下降趋势。当摆动频率增加到120 Hz和150 Hz时,断裂区域由母材转变为热影响区。
TC4 titanium alloy welded joints were remelted by oscillated laser welding,and effect of oscillated frequency on porosity,microstructure,and mechanical properties of TC4 titanium alloy welded joints was studied.The results showed that remelting oscillated laser welding could effectively eliminate porosity defects of TC4 titanium alloy welded joints.With the increase of oscillated frequency,effect of eliminating porosity was enhanced,and elimination effect of large porosity became more pronounced.In remelting oscillated laser welded joint,microstructure of weld was acicularα'martensite and part ofαphase,and microstructure of heat-affected zone was composed of primaryαphase,acicularα'martensite andβphase.With the increase of oscillated frequency,stirring effect of laser on molten pool was enhanced,grains in weld gradually broke and became finer,while grains growth in heat-affected zone became more favorable and grains gradually became coarser.The increase of oscillated frequency changed microstructure of welded joints and lead to performance variation of welded joints.Increasing oscillated frequency changed microstructure of welded joints changed,and then changed mechanical properties of welded joints.With the increase of oscillated frequency,hardness in weld of TC4 remelting welded joints increased,while hardness of heat-affected zone gradually decreased,and tensile properties of welded joints showed a downward trend.When oscillated frequency increased to 120 Hz and 150 Hz,fracture area changed from base metal to heat-affected zone.
作者
张骞
张成竹
林波
冉洸奇
胡世天
朱宗涛
Zhang Qian;Zhang Chengzhu;Lin Bo;Ran Guangqi;Hu Shitian;Zhu Zongtao(Chengdu Aircraft Industrial(Group)Co.,Ltd.,Chengdu 610031,China;Southwest Jiaotong University,Chengdu 610031,China)
出处
《焊接》
北大核心
2023年第1期55-59,共5页
Welding & Joining
关键词
钛合金
重熔摆动激光焊
气孔
组织
力学性能
titanium alloy
remelting oscillated laser welding
porosity
microstructure
mechanical properties
