Welding Process Optimization And Numerical Simulation Of Aluminum Template Using MIG Welding

With the rapid development of China’s urbanization, urban residential building increasingly onerous, aluminum alloy template as a new type of energy-saving environmental products, for its high efficiency, long service life and low overall cost and other advantages are widely used. Due to the larger number of aluminum alloy template size and dense welds, resulting in the welding deformation. For the fabrication of certain 6061-T6 aluminum alloy template, influence of process parameters on microstructures and mechanical properties of welded joint of MIG,through the finite element method to simulate the welding process of the structure,analysis of deformation, optimization of welding process, providing a basis for application of MIG welding on the aluminum alloy template.Firstly, the MIG welding process and mechanical properties test was carried out.The results indicated that with an increase in welding line energy, the width of heat affect zone increasing from 320 Pm to 740 Pm and grain size in the weld fusion zone increasing from 44 Pm to 63 Pm. Partial porosity presented at low line energy and resulted in low the mechanical properties of the joints. Bad wire feed speed made the weld forming and welding process was not stable, the highest ultimate tensile strength value was 239 MPa which was gained at 8.2m/min.Secondly, a numerical model was carried out to simulate the temperature field and the welding deformation of the 6061-T6 aluminum alloy specimens. The results showed that the simulated values eventually had a good match with the actual measured values, which verified the reliability of the model.Through simulated the welding process with partial model and comparing the welding deformation of partial model under different welding sequence. The results showed that symmetrical welding form the middle to both sides of the components, can effectively controlled deformation. The cooling time between welds has no significant effect on the welding deformation, and the less cooling time after welding not only saved the computation time, but also can greatly improved the production efficiency.Based on this premise, imposed a certain rigid constraints can further reduced the welding deformation, so we designed a special welding fixture.At last, the welding deformation of integral structure was simulated, Specific studied the welding sequence of I-beam and the optimum welding program was propose. The results indicated that symmetrical welding form the both sides to the middle of6061-T6 aluminum alloy template had the smallest deformation. With this sequence,the welding fixture can significantly reduced the concave deformation of panel. The simulation results could reduce the 6061-T6 aluminum alloy template MIG welding production cycle, improving the labor production efficiency and reducing costs.