基于冷金属过渡焊接的铝合金增材制造工艺研究  

Aluminum alloy additive manufacturing process based on cold metal transfer welding technology

作　　者：李景乾 菅晓霞 万文轩 LI Jingqian;JIAN Xiaoxia;WAN Wenxuan(School of Mechanical and Electrical Engineering,Wuhan Institute of Technology,Wuhan 430205,China;Hubei Research Center of Intelligent Welding Equipment and Software Engineering Technology,Wuhan 430205,China;China National Nuclear Industry Corporation 404,Jiayuguan 735100,China)

机构地区：[1]武汉工程大学机电工程学院,湖北武汉430205 [2]智能焊接装备与软件工程技术湖北省研究中心,湖北武汉430205 [3]中核四0四有限公司,甘肃嘉峪关735100

出　　处：《武汉工程大学学报》2024年第6期657-662,675,共7页Journal of Wuhan Institute of Technology

基　　金：国家自然科学基金(51705133)。

摘　　要：5183铝合金具有优异的比强度、比刚度及耐腐蚀性能,在航空航天及交通运输领域应用广泛。使用增材制造技术加工5183铝合金构件在缩短周期、降低成本等方面具有显著优势,但是目前采用丝弧增材工艺制造的铝合金具有表面精度低、力学性能不佳等问题。本文采用基于冷金属过渡焊接的工艺制造5183铝合金薄壁件,研究工艺参数对增材形貌及力学性能的影响规律。结果表明,当焊接速度为7 mm/s、焊接电流为110A时,焊缝表面光滑,成形系数λ接近1,是所选范围内最优的焊接工艺参数。沉积态铝合金中下部区域层内晶粒组织以细小的等轴晶为主,而层间晶粒有枝晶破碎和晶粒粗化现象。所选取试样在水平方向和竖直方向上的平均抗拉强度分别为245.2、211.7 MPa,各向异性特征不明显,平均断后伸长率分别为19.5%和10.3%,高度方向塑性较差。试样拉伸断口位于层间结合区域,在气孔侧壁上分布有很多细小的微裂纹,证明气孔与裂纹降低了铝合金承载外部载荷的能力,同时也增加了构件的开裂倾向。The 5183 aluminum alloy exhibits exceptional specific strength,specific stiffness,and corrosion resistance,making it a widely applied material in aerospace and transportation industries.Utilizing additive manufacturing technology for processing 5183 aluminum alloy components offers notable advantages in terms of production cycle and cost reduction.However,current aluminum alloys produced using the wire arc additive processes suffer from issues such as low surface accuracy and poor mechanical properties.This study focuses on the fabrication of thin-walled 5183 aluminum alloy components using cold metal transfer additive manufacturing.Through experimentation,optimal welding parameters were determined,to investigate their influence on morphology and mechanical performance of manufactured additives.Findings reveal that at a welding speed of 7 mm/s and a welding current of 110 A,the weld seam exhibits a smooth surface,with a forming coefficientλclose to 1,representing the optimal welding parameters within the specified range.Microstructural analysis indicates that the middle and lower regions of the deposited 5183 aluminum alloy predominantly feature fine equiaxed grains,while interlayer grains display varying complexities in size,type,and orientation,accompanied by dendrite fragmentation and grain coarsening phenomena.The average tensile strength of the selected samples in the horizontal and vertical directions is 245.2 and 211.7 MPa respectively,with fracture elongation rates of 19.5%and 10.3%,respectively,and the plasticity is relatively poor in the vertical direction.Tensile fractures occur at interlaminar bonding areas,revealing numerous fine microcracks along the sidewall of the pores,which suggests that pores and cracks compromise the load-bearing capacity of the aluminum alloy,exacerbating the propensity for cracking of the components.

关 键 词：电弧焊接 快速成型 铝合金 力学性能 

分 类 号：TG444[金属学及工艺—焊接]