An Analytical Study on Laser Forming Process of Sheet Metals, Using New Elasto-Plastic Temperature Dependent Material Model

Abstract:

The laser forming process is one of the last technologies on forming of sheet metals with laser beam heat distribution. In this process laser beam moves across the top surface of the sheet metal and the heated zone expands and causes a great moment that deforms the sheet metal. Subsequently, the heated zone gets cooled and provides a reverse strain and moment. The final bending angle is a combination of two phases. Due to the complexity of the process, it is studied with different approaches; FEM analysis and analytical as well as empirical methods. The laser forming is a sensible process regarding the material properties. Also, because of the temperature change during the process, it is important to use a temperature dependent model. In this study The FEM model is proposed for simulation of the mechanism. Based on the simulation results, an integrated analytical model is then developed by a new elasto-plastic material model considering linear strain hardening, combined with the temperature dependent mechanical and physical properties. In addition, the temperature dependent tangential modulus is used instead of the yield point of the material to improve accuracy in the plastic deformation phase. Finally, the analytical model is compared with the FEM standard code, which showed a great conformity.

• Periodical: Advanced Materials Research (Volumes 622-623)
• Pages: 569-574
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.622-623.569
• Online since: December 2012
• Authors: Shams Torabnia, Afshin Banazadeh
• Keywords: Analytical Model, Finite Element Method (FEM), Laser Forming, Thermo-Elasto-Plastic

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