Electron Beam Welding of Aluminium Alloy AW2099

The paper deals with the analysis of mechanical properties of welded joints made of AW 2099 aluminium-lithium alloy by electron beam welding. The thickness of the experimental material was 3±0.2 mm. PZ EZ 30 STU electron beam welding machine was used for production of welds. Maximum accelerating voltage used within this study was 55 kV. Metallographic analysis, hardness measurement test and static tensile were carried out. The structure of the weld joint of aluminium-lithium alloy was investigated. Produced welded joints were characterized by the presence of following zones: heat affected zone (HAZ), equiaxed non-dendritic zone (EQZ), columnar dendritic zone (CDZ) and equiaxed dendritic zone (EDZ). EQZ grains were formed due to heterogeneous nucleation on precipitates at the fusion boundary. EQZ is typical for joining of aluminium lithium alloys.