摘要: |
针对Al-Zn-Mg-Sc铝合金进行真空电子束焊接试验,研究表明,焊接接头各区域显微组织有所变化,与母材相比,热影响区晶粒有所粗化,且晶粒内部弥散分布的Al3Sc粒子数量有所减小,焊缝区发生了再结晶,由母材细长的纤维状组织转变为等轴晶组织,Al3Sc粒子发生了溶解,且焊缝上部的晶粒尺寸明显大于焊缝中部的晶粒。拉伸试验结果表明,焊接接头抗拉强度达到基材强度的80%以上,大部分拉伸试样均在焊缝处断裂,退火态焊接接头经过焊后时效处理,接头强度可达515.7MPa,为母材的94.2%,有效地提高了焊接接头的抗拉强度。 |
关键词: 真空电子束焊接;Al-Zn-Mg-Sc铝合金;Al3Sc相 |
基金项目: |
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Study on Microstructure and Property of Al-Zn-Mg-ScAluminum-alloy Joints Welded by Vacuum Electron Beam |
Hu Chunhai Qin Zhanling Wu Jun
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Xi’an Aerospace Power Machine Factory, Xi’an 710025
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Abstract: |
In this paper, Al-Zn-Mg-Sc aluminum-alloy was welded by Vacuum Electronic Beam Welding (EBW). The results showed that, microstructure varied in different regions of welded joint. Compared with the base metal, the grains of Heat Affect Zone got coarsening, and the quantity of Al3Sc particles which dispersively distributed in grains had decreased. The weld zone occurred recrystallization, and generated equiaxial grain structure, Al3Sc particles dissolved in this area, and the size of grains on the top of weld is larger than that in the center of weld. The tensile test results indicated that, the tensile strength of welded joints is higher than 80% of base metal, most of tensile samples of welding joint break in weld zone. The tensile strength of as-annealed welding joints can reach 515.7MPa, 94.2% of base metal when the joints have the post welding aging treatment (PWAT), and the tensile strength of welded joints is enhanced effectively. |
Key words: Vacuum Electronic Beam Welding;Al-Zn-Mg-Sc aluminum-alloy;Al3Sc phase |