Research On Process And Performance Of Aluminum Alloy Parts By Laser Induced Arc Additive Manufacturing

Aluminum alloy has many excellent properties such as low density,high strength,highplasticity,high electrical conductivity,and high thermal conductivity.It has a wide range of applications in aviation,aerospace,transportation,and machinery manufacturing.Compared with the traditional manufacturing process,additive manufacturing technology is a bottom to top manufacturing process,which can greatly reduce the waste of materials and shorten the production cycle.It can make some complex shape parts that traditional processing methods can't make.Compared with laser or electron beam additive manufacturing technology,arc additive manufacturing technology has lower manufacturing cost and higher production efficiency,but its products have lower dimensional accuracy and unstable performance.In order to solve the problems existing in the process of arc additive manufacturing and explore the methods to improve the mechanical properties of additive samples,this paper conducts related research on 2319 aluminum alloy additive manufacturing based on low-power pulsed laser-induced MIG arc.The influence of laser power and subsequent heat treatment process on the additive structure was analyzed in terms of microstructure and mechanical properties.The main research contents and conclusions are as follows:This article first studies the influence of different process parameters on the formation of a single-pass single-layer bead.With the increase of the stacking current,the penetration depth and width of a single-pass single-layer bead gradually increase.With the increase of stacking speed,the penetration depth and width of a single-pass single-layer weld bead gradually decrease.Through the analysis of the appearance forming quality and the residual height coefficient of a single-pass single-layer weld bead,the best process parameters when using a single arc as a heat source were explored.After adding a pulsed laser,by changing the size of the laser power and comparing it with no pulsed laser,the appearance and forming quality of the additive thin-walled wall has been significantly improved,and the material utilization rate has also been significantly improved.With the increase of laser power,the width of the top layer and the height of the wall gradually become stable,the average width of the top layer gradually decreases,and the height of the wall gradually increases.The pulsed laser makes the grain size inside the additive specimens finer and reduces the porosity.The tensile property in the horizontaldirection is better than the vertical direction.The fracture mode of the tensile sample is ductile fracture.Pulse laser can effectively improve the tensile strength,elongation after fracture and microhardness of the additive wall.The heat treatment process used in this experiment was determined and the influence of heat treatment process on the structure and properties of the additive specimen was investigated.By comparing the appearance of the additive wall before and after the heat treatment,it is found that the appearance size has hardly changed.After heat treatment,the dendrite structure in the top region is significantly reduced,and the eutectic structure at each location becomes smaller.The original strip-shaped eutectic structure is dissolved in a large area,and the heterogeneity of the eutectic structure is greatly improved.The tensile strength and microhardness of the wall have been significantly improved.Through the above research to better promote the application of this technology in the field of manufacturing.