2219 T852过渡环与T87箱筒段电子束焊接接头性能

基于贮箱用2219 T852整体过渡环与T87箱筒段的电子束环焊缝,开展了部段级电子束焊接接头常、低温力学性能测试,同时对焊接接头错缝量、断裂类型及金相组织进行了分析。研究结果表明:部段级常、低温2219 T852与T87电子束焊接接头的强度影响系数为0.63,低温状态下焊接接头的力学性能比室温状态下有所提高;错缝量与焊接接头力学性能成反比,其中对延伸率影响最为显著,低温有助于缓解错缝对焊接接头力学性能的弱化影响;电子束焊接接头组织不均匀性和结构形貌上的不连续性,特别是T852侧热影响区晶粒粗大,导致T852侧热影响区和焊缝接头根部为电子束焊缝的薄弱区域,焊接接头极易在该区域发生断裂。

Mechanical Properties of Electron Bean Welded Joints on 2219 T852 Transition Ring and T87 Shell Section

Based on the electron bean circular weld on 2219 T852 transition ring and T87 shell section used for tank, the normal and low mechanical properties of the electron beam welded joints in the segment level were tested, and the staggered amount,fracture types and microstructure of the welded joints were analyzed. The following conclusions can be drawn.The normal and low strength effect coefficient of the segment level electron beam welded joints on 2219 T852 transition ring and T87 shell section are 0.63, and relative to the normal temperature, the low temperature mechanical properties of welded joints have been improved. The staggered amount is inversely proportional to the mechanical properties of welded joints,and it has the most significant effect to elongation, and low temperature should help to ease the weakening effect of staggered to the mechanical properties of welded joints. Because of the uneven tissue and the discontinuous structure of the electron beam welded joints,especially T852 side heat affected zone with coarse grains,the T852 side heat affected zone and the roots of welded joints are the weak area of the electron beam weld, and welded joint is easy to fracture in the area.