Laser forming process is used to form metal sheet in more or less complex three-dimensional shapes with good results for small-medium series or prototypes realization, due to its remarkable flexibility, precision, and no-dies need. The process is not yet well understood and for this purpose finite element analysis is a good and cheap tool. The spot dimension is a very important process parameter, it is related to the power density distribution on the surface of the processing material and influences heat transfer, stress and strain distribution, and the radius of curvature of the final product. In this paper a numerical investigation on the influence of spot dimension on temperature field, deformation field and material properties is presented. The process is modelled as a thermo-mechanical coupled problem; geometric and material nonlinearity, convective-radiative boundary conditions, and Gaussian power density distribution into the laser beam spot are considered. A different spatial discretization is proposed, for each spot dimension to material thickness ratio, to optimize mesh, to obtain good accuracy, and to reduce computational time. Numerical results are compared with experimental data.
A Finite Element Analysis of the Laser Forming Process: Influence of Spot Dimension on Discretization, Temperature, and Deformation Field
CARLONE, PIERPAOLO;PALAZZO, Gaetano Salvatore;PASQUINO, Raimondo
2005-01-01
Abstract
Laser forming process is used to form metal sheet in more or less complex three-dimensional shapes with good results for small-medium series or prototypes realization, due to its remarkable flexibility, precision, and no-dies need. The process is not yet well understood and for this purpose finite element analysis is a good and cheap tool. The spot dimension is a very important process parameter, it is related to the power density distribution on the surface of the processing material and influences heat transfer, stress and strain distribution, and the radius of curvature of the final product. In this paper a numerical investigation on the influence of spot dimension on temperature field, deformation field and material properties is presented. The process is modelled as a thermo-mechanical coupled problem; geometric and material nonlinearity, convective-radiative boundary conditions, and Gaussian power density distribution into the laser beam spot are considered. A different spatial discretization is proposed, for each spot dimension to material thickness ratio, to optimize mesh, to obtain good accuracy, and to reduce computational time. Numerical results are compared with experimental data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
