Jean-Marc Roelandt

Simulation of Forming Processes, with Friction, Coupling Finite Elements and Boundary Elements

Nowadays, the simulation of forming process is rather well integrated in the industrial numerical codes. However, in order to take into account the possible modifications of the tool during rates of working, a dedicated numerical software is currently developed within the Laboratory Roberval. This one more uses coupling finite elements and boundary elements for the respective modelling of the part and the tool. This software will more particularly allow the identification of the fatigue criteria of the tool. The optimal shapes of tools could also be conceived for increase their lifespan and the manufactured part could have the required quality.

Numerical and experimental investigations into Tailored Welded Blanks formability

A Tailor welded blank (TWB) technology gives automotive designers the ability to selectively vary body panel thickness and alloy to optimize the use of material. TWBs offer several notable benefits including decreased part weight, reduced manufacturing costs, increased environmental friendliness, and improved dimensional consistency. In order to take advantage of these benefits, however, designers need to overcome the formability of TWBs and be able to accurately predict unique characteristics related to TWB forming early in the design process. In this paper, a numerical model to predict the forming height dome and a specific forming curve of TWBs is presented. Finite element analyses of standard TWB forming tests (Nakazima) were performed in Arcelor Mittal Auto Application Research Center to determine the interaction between the weaker and the stronger materials. To measure the critical strain at necking a numerical method is used. A comparison of numerical and experimental results highlights a good agre...