BT22高强钛合金电子束焊接工艺研究

The Research on Electron Beam Welding Procedure for BT22 High Strength Titanium Alloy

为研究BT22高强合金电子束焊接工艺,分别调整电子束流、聚焦电流等工艺参数对焊缝成形进行研究,并对焊后未经热处理状态和热处理过后的金相试样进行组织观察与分析。对经过热处理的焊接试样进行了显微硬度测试和拉伸性能测试。研究表明,最佳的焊接工艺参数为高压U=-60 kV,灯丝设定I_灯=650 mA,运动速度v=3 mm/s,工作距离D=295 mm,电子束流I_b=22 mA,聚焦电流I_f=680 mA。在焊缝区和热影响区的晶粒中析出细小的α片,同一集束的α片的趋向为各向同性。α片具有强化和降低β过饱和的作用,母材的晶内α片粗大。母材的硬度值高于焊缝区域,接头平均拉伸性能为938.4 MPa。

To study the electron beam welding procedure for BT22 high strength titanium alloy,this paper adjusts the electron beam current,focused-current,the welding procedure parameters and the appearance of the weld,observes and analyzes the microstructure of metallographic specimens:one is heat treatment specimen and another is not.The microhardness and tensile property of the heat treatment specimen are tested.The research result shows that the optimal welding parameters is U=-60 kV,I=650 mA,v=3 mm/s,D=295 mm,I b=22 mA,I f=680 mA.There are some fineαslice in the weld joint and HAZ,αslice in the same beam tends to the same.Theαslice can act for strengthening and reducing supersaturation ofβ.Theαslice is thick in base metal.The microhardness of the base metal is higher than one in the weld joint.The average tensile property of the joint is 938.4 MPa.