铝合金5083和5052的激光焊接

通过工件表面焊前准备状态、接头形式和焊接工艺参数对焊缝形状的影响，分析了铝合金５０８３与５０５２在相同焊接条件下的激光焊接相同点和不同点；通过焊缝截面形状和微观组织的观察，得到了焊接条件对焊缝表面下凹度和胞状树枝晶间距的影响趋势，观察到在本实验条件下的焊缝组织主要由胞状树枝晶的一次组织和二次组织组成；通过电子探针（ＥＰＭＡ）法对焊缝主要合金元素Ｍｇ含量分布及微观偏析的测定，认为Ｍｇ的蒸发损失受到焊接条件的影响；显微硬度的分布状态表明，焊接中Ｍｇ的分布及含量决定了显微硬度的分布与大小，而且Ａ５０８３和Ａ５０５２熔化区显微硬度分别大于母材值的９１％和９３％。

Laser Welding of 5083 and 5052 Aluminum Alloys

The influence of the preparetion of workpiece surface before welding , the shapeof joint and welding process parameters on the geometry of weld bead was investigated and the same and the different point of laser welding for aluminum alloys 5083,5052 at the same welding condition were discussed;Through the observation of the shape of weld section and micrstructures,it was found that the microstructures of weld bead mainly consisted of the primary cellular dendrites and the secondary grains,the concavity of weld bead and the inter-val of cellular dendrites were affected by weld condition. The EPMA result of distributionand the microsegrgationof Mg in weld bead indicated that the loss due to evaporation of alloy element Mg was contorlled by welding condition. The distribution of microhardnesswas by determined distribution of Mg content. The Vickers hardnesses of weld bead of aluminum aL-loys 5083,5052 were more than 91 and 93 percent that of base metal respectively.