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The increasing use of superalloys in the industry brings new issues to forging manufacturers concerning Finite Element analysis of the forming process. Once we consider high performing materials, significant differences can occur between numerical and experimental results. The lack of knowledge about materials and thermal exchanges explains a part of these differences but it has been shown that the machine behavior has a significant impact on the forging process. Press modelling is a way to quantify the energy dissipated in the machine structure and improve simulations. This study is a first step in the screw press modelling. Starting from an approximation of the press geometries, a purely static elastic (PSE) model is developed and a numerical simulation considering only uprights is performed. Uprights stiffness predictions from the PSE model and the FE simulation are compared and the PSE model is validated. Then, the press is approximated by a portal frame and FE simulation is realized to determined uprights stiffness by considering links effects and bending behaviors in the structure. Comparison with experimental results validates the approximation. [ABSTRACT FROM AUTHOR]

Cross wedge rolling (CWR) is a metal forming process used in the automotive industry. One of its applications is in the manufacturing process of connecting rods. CWR transforms a cylindrical billet into a complex axisymmetrical shape with an accurate distribution of material. This preform is forged into shape in a forging die. In order to improve CWR tool lifecycle and product quality it is essential to understand tool wear evolution and the physical phenomena that change on the CWR process due to the resulting geometry of the tool when undergoing tool wear. In order to understand CWR tool wear behavior, numerical simulations are necessary. Nevertheless, if the simulations are performed with the CAD geometry of the tool, results are limited. To solve this difficulty, two numerical simulations with FORGE® were performed using the real geometry of the tools (both up and lower roll) at two different states: (1) before starting lifecycle and (2) end of lifecycle. The tools were 3D measured with ATOS triple scan by GOM® using optical 3D measuring techniques. The result was a high-resolution point cloud of the entire geometry of the tool. Each 3D point cloud was digitalized and converted into a STL format. The geometry of the tools in a STL format was input for the 3D simulations. Both simulations were compared. Defects of products obtained in simulation were compared to main defects of products found industrially. Two main defects are: (a) surface defects on the preform that are not fixed in the die forging operation; and (b) Preform bent (no longer straight), with two possible impacts: on the one hand that the robot cannot grab it to take it to the forging stage; on the other hand, an unfilled section in the forging operation. [ABSTRACT FROM AUTHOR]

For electromagnetic applications the microstructure and the final mechanical state are key parameters. These can be obtained by a judicious choice of the material, a particular design like laminated steels but also through the determination and the mastering of the fabrication process. This present paper contains a brief introduction to electromagnetics and the qualification of a "good" electromagnetic quality. Then the article highlights, based on literature, first the influence of the process parameters on microstructure, mechanical state and secondly the impact these properties themselves on magnetic properties. Eventually, a methodology is proposed in order to predict the functional behavior of a part in its final system, taking into account its manufacturing process. The academic study case presented here can illustrate such a methodology. This kind of methodology includes in particular experimental tests, physical analysis and numerical modeling. [ABSTRACT FROM AUTHOR]