Journal of Welding Science

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In this paper, laser beam welding of a rectangular piece of steel was simulated using Fluent software. Physical properties of analytical field was constant and its changes with temperature was ignored. In the present work, effect of tool speed and laser power on temperature distribution of workpiece surface and different deeps in the plane of symmetry and also maximum of temperature and depth of penetration were investigated. Using a macro code, geometry generation and meshing of the analytical field by helping required geometric  parameters were provided for software. Moreover, laser radiation power was exerted by writing an UDF in the fluent software. In this case, it was assumed that the workpiece is stationary and gaussian thermal source model defined in UDF moves with the intended speed. Results show that at a constant power, maximum temperature of the workpiece decreases with increasing heat source speed, moreover, in this case, gradient of temperature in front of the workpiece and behind of it, increases and decreases respectively. It is found that the temperature in the depth of the workpiece increases with increasing the power.

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Aluminum to stainless steel joints are broadly used in industries in order to reduce fuel consumption. While fusion welding is not a suitable method to join these metals. solid state welding, like friction welding (FW), is an effective way to this process. However, risk of intermetallic compounds (IMCs) formation is probable in these welds. In previews investigations formation of FeAl₃, Fe₂Al₅ and Fe₄Al1₃ is reported. In this study, effect of different parameters on generated heat and temperature distribution that lead to formation of these compounds in a FW of aluminum alloy to stainless steel is investigated using Finite Element Method (FEM). Additionally, a mathematical modeling of the parameters is performed using Artificial Neural Network (ANN) and the optimum level of the parameters has been found.

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In this study, the effect of tool's advance velocity on the mechanical behavior of the Al-7075 alloy during friction stir welding was simulated. In this simulation, the Lagrangian method with rigid-Visco-plastic material was used. The results of the process temperature obtained by the simulation method were verified by the experimental welding test. Using the characteristic stress, strain and temperature relationships in the Al-7075 alloy, the changes and the relationship between the material strength during the welding process by simulation was studied. The generated simulation defects was verified by experimental test.