![]() Simulation using different cutting edge preparations, namely sharp edge, small hone, large hone, chamfer and different combinations of hone plus chamfer, are conducted to obtain residual stress profile on the machined surface. Special attention is paid to the effect of cutting edge preparation on the beneficial as well as the penetration depth of the residual stress in the machined surface. In this paper, the effects of workpiece hardness, tool geometry as well as cutting conditions on the residual stress distribution in the hard machined surface are investigated using a newly proposed hardness-based flow stress model employed in an elastic-viscoplastic FEM formulation. The prediction of residual stress profile in the machined surface is difficult due to the lack of proper material model to depict the material behavior and the complex interaction among the. Residual stresses in the machined surface and the subsurface are affected by cutting tool, workpiece, tool/workpiece interface, and cutting parameters, such as feed rate, depth of cut and cutting speed. In less favorable cases, the method could be combined with a reduced order model method such as the hyper-reduction method. The results show a good error/computation time ratio, which shows the effectiveness of the proposed method. We have compared the results to experimental data. So far, the method has been successfully applied to a Overlay welding repair industrial case. Finally, we add the translated incrementation field and the m-th field on the welding region to obtain the whole prediction. ![]() This assures that the increase that occurs on the m-th weld bead now happens on the new (m+1)th weld bead. To do so, we translate the field a distance d in the right sense, with d being the distance between two weld beads. On the welding region we need to take into account that a new weld bead appears. On the border region, we add the m-th pass field and the incrementation field to approximate the (m+1)th field. We divide the domain in two different regions: the border region and the welding region. This field gives the evolution of strain and stress from the (m-1)th pass to the m-th. We call this field, the incrementation field. The first step is to compute a field containing the difference between the m-th and (m-1)th pass. We make the assumption that the differences observed between the m-th and the (m-1)th pass are similar to the ones that will appear between the (m+1)th and the m-th pass. The objective is to obtain a prediction of the m+1 pass using the data of the m and m-1 passes. In order to use the method, we need to compute the first m passes. We propose a simplified method called Physical Fields Shift which allows us to accelerate the computations and obtain an approximation of the strain and residual stress state after the repair process. ![]() To study many industrial cases, we would like to apply simplified methods to compute the simulations. Bearing in mind that the simulation of a single pass takes around 10 hours, we immediately realize that the simulation of the whole process using the finite elements method is not feasible with reasonable delay. In this kind of process, more than an hundred passes over two different layers of weld beads are required. An example of this kind of problem is the simulation of a welding repair process called Overlay. This large number of passes implies an even greater time expense and thus their study through simulations is almost impossible to achieve in the industry. In some industrial cases of welding repair, a large number of passes is involved. The numerical simulation of welding processes is an extremely complex problem because of the strong non linearities of the physical models, the spatio-temporal dimensions of the problem.
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