Research On Bypass-Current Of Plasma-MIG Hybrid Welding Process Of Marine Aluminum Alloys

In recent years,with the rapid development of science and technology and industrial level,traditional manufacturing industry has continuously transformed and upgraded,and the shipbuilding industry has also developed in the direction of lightweight structure,green environmental protection,energy saving and emission reduction.Among them,the lightweight structure is the key to the green manufacturing of the shipbuilding industry.Traditional ship construction materials are difficult to meet the requirements of lightweight structure due to their own characteristics.Therefore,high-performance and high-quality construction materials such as aluminum alloys are more and more widely used in ship structure construction.Aluminum alloy has the advantages of small elastic modulus,high strength,good corrosion resistance,and easy processing,which can meet the needs of shipbuilding.The application of aluminum alloy inevitably involves the welding of aluminum alloy.Traditional MIG welding cannot take into account high efficiency,precision and high quality when welding aluminum alloy,which makes it difficult for aluminum alloy to be widely used in shipbuilding.Therefore,the development of new high-efficiency and high-quality welding processes can promote the application of aluminum alloy in the field of ships,improve production efficiency and ship construction quality,and promote the development of the industry.Aiming at the shortcomings of the traditional welding process of aluminum alloy,this paper adopts the Bypass-Current of Plasma-MIG Hybrid Welding Process.This process combines the high efficiency of MIG welding,the restriction of plasma arc and the bypass shunt to reduce heat input and other technical advantages,which can realize high-quality and highprecision welding.This paper uses Bypass-Current of Plasma-MIG Hybrid Welding Process to carry out surfacing and butt welding tests on 5mm thick 5083 aluminum alloy.Orthogonal analysis of the influence of different welding parameters on the macro morphology of the weld,the mechanical properties of the weld joint and the detection of pore defects,and the physical characteristics of the coupled arc and the droplet transfer mode under the action of the coupled arc are analyzed.Compared with traditional MIG welding and plasma restrained MIG welding,the technological superiority of Bypass-Current of Plasma-MIG Hybrid Welding Process is analyzed.The test results show that under the optimal welding parameters,high-quality welding of5 mm thick 5083 aluminum alloy can be achieved.Comparing the strength of the joints,it is found that the strength of the butt joint is relatively high.The average tensile strength of the joint is 289 MPa,which is more than 90% of the base metal strength.The method is ductile fracture,and the weld porosity is less than 0.1%.During the welding process,the coupled arc shape is stable,and the arc pressure distribution in the weld pool is uniform.The droplet transfer modes are short-circuit transfer and droplet transfer.In the droplet transfer mode,the welding process is stable and the weld formation is better.