7A52铝合金电子束焊接参数及性能

对20mnrl厚7A52铝合金板材采用试件法进行电子束焊接，确定了焊接参数并对力学性能进行分析．结果表明，采用加速电压60kV，电子束流120mA，聚焦电流763mA，焊接速度800mm／min，可得到良好的焊缝表面．电子束流增大焊缝深宽比显著增加，聚焦电流微小的数值变化可引起焊缝形状突变．接头焊缝区晶粒细小均匀，抗拉强度为母材的87％，焊缝维氏硬度最低值为母材的61％，焊缝冲击韧度为母材的95．4％，表明了电子束接头的性能很高．

Welding parameters and mechanical properties of electron beam welding of 7A52 aluminum alloy

The electron beam welding of 20 mm 7A52 aluminum alloy plates was conducted.The welding parameters were determined by the method of multiple specimens and the mechanical properties of the joints were examined.The results showed that the satisfing weld appearance can be achieved when the accelerating voltage was 60 kV,electron beam current was 120 mA,focus current was 763 mA and welding speed was 800 mm/min.The ratio of depth to width obviously increased with the increase of electron beam current.Tiny alteration of focus current caused significant change in the weld shape.Fine and uniform grains occurred in the weld seam,and the fracture strength,weld hardness and impact toughness of the joint reached 87%,61% and 95.4% of those of base metal,respectively.