Partial Penetration Welding Of 5A06 Aluminum Alloy With High Power Fiber Laser Insert

With good corrosion resistance, high strength ratio, and good welding performance after annealing,5A06 aluminum alloy has been widely used in aviation, aerospace, automobile, chemical industry and other occasions. In the field of aerospace, partial-penetration welding is widely used in order to ensure the working environment of internal components in the cylinder,when weld the stiffener of the cylinder, the surface of arc riveting joint is greatly raised and the interior of the cylinder is easy to deform. And the lap joint not only waste material but also increase the weight of the part.Laser has excellent transmission and focusing properties. Compared to arc,laser can achieve very high power density, very fast welding speed, and the heat input is very low, the heat affected zone and the deformation of the joint is very small, laser can not only be used in spot welding, but also can easily achieve continuous welding, the mechanical properties of laser welding joint is much better than spot welding.(1) In order to ensure the surface quality and mechanical properties of partial-penetration laser welding joint,this paper use 6kW high power fiber laser to research the partial-penetration welding of 5 A06 aluminum alloy on numerical simulation and experiments. And introduce the domestic and foreign status of laser welding of aluminum alloy, partial-penetration laser welding and its numerical simulation research status.The types of the aluminum alloy and the difficulties of laser welding of aluminum alloys are also introduced.(2) This paper consider the characteristics of molten pool in laser deep penetration welding, choose suitable heat source model, and consider the thermo physical properties of the material and boundary conditions,use large general finite element software AN SYS, simulate the temperature field and stress field in the process of partial-penetration laser welding of 5A06 aluminum alloy, studied the thermal cycling conditions and stress distribution during welding process.(3) This paper carried out the experiment of partial-penetration laser welding of 5A06 aluminum alloy. In a fixed laser power and positive welding protective gas condition, by changing the single welding parameter, study the effects of welding speed, defocusing amount, lap plate gap on the quality of the weld surface. And analysis the micro structure and mechanical properties of partial-penetration laser welding joint after parameters are optimized, compared the strength of laser welding joint with arc riveting joint,witch is commonly used in industry nowadays.