| Because of the 2025 made in China,technological innovation and green development have become the core issues of the manufacturing industry.With the characteristics of energy saving and emission reduction,the light weight of the product has received extensive attention from the manufacturing industry.The metal sandwich plate is a new type of lightweight hollow sandwich structure with two panels and one core plate.It has been widely used in the market because of its high strength and high specific stiffness.But the market is now making sandwich panels by laser welding.The width of the core plate of the sandwich plate made by laser welding is less than that of the panel,which leads to the stress concentration and the strength and toughness of the whole plate.Aiming at the problem of laser welding,this paper innovative applies flux sheet restraint arc technology to the manufacture of sandwich structure.A new technology is put forward to manufacture high strength steel sandwich panels by welding arc welding.In this paper,the factors affecting the special T joint process of BS960 high strength steel sandwich plate welded by arc plug welding with flux sheet are studied.To eliminate the influence of assembly accuracy and equipment on weld formation,a simple comparative experiment is adopted in this paper.Through a large number of process welding tests,the influences of current parameters,such as current,voltage,groove gap and welding accuracy on weld formation are explored.Research discovery : 1,the motion precision of welding wire is less than + 0.5mm,which can prevent the occurrence of lateral leakage.2,With the assembly gap 5-6mm,the welding process is stable and the T joint weld is formed well.3,when the current is determined,with the arc voltage increasing,the joints present "unsoldered","formed well",and the arc's another climbing "unsoldered" and "welding leakage" in succession.4,when the arc voltage is fixed,with the increase of the welding current,the penetration and leakage probability of the T type joint show a step increase.5,the optimum range of technology is: voltage 20-24 V and current 160-300 A.In this process,well penetration and good shape of weld shape can be obtained.The shape of arc combustion and the change process of molten poolare studied by high speed camera technology,and the forming mechanism of the weld is explored.Research discovery : 1,the distance between the welding flux and the arc affects the shape of the arc and the quality of the weld in the welding process.2,the droplet transfer form into short circuiting,arc in narrow width horn,conducive to droplet transport and root fusion.3,the special shape of the arc and the comprehensive effect of short circuiting transition make the T type joint form a typical U weld shape.The fine texture and mechanical properties of T type joints were tested.Research discovery : 1,the parent material area consists of strip fine grain pearlite and ferrite.The microstructure of the weld is acicular ferrite.Coarse-grained regions are produced near the fusion line.The heat affected zone is mainly composed of bainite and ferrite near the weld zone,and the main area of the heat affected zone is pearlite and ferrite near the base area.2,there is no softening in the heat affected zone,and the hardness distribution in the center of the weld is stable.3,both the bending test and the shear test show that the arc plug welding is significantly better than the laser welded sandwich plate. |
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