Semi-static modeling of laser utilization in thermal forming simulations

• Applicant: Professor Dr.-Ing. Frank Vollertsen
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2013 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 232757878

The induction of plastic form changes by the utilization of the laser beam is a flexible method to form simple bended parts as well as complex geometries. This effect may be even used in chains of production processes as an additional compensating interim-step to minimize the distortion resulting from the manufacturing steps. Large changes to the form are mostly reached by a multiple number of irradiation cycles along the bending edge (incremental process). Numeric calculation methods like the finite element method (FEM) are sufficiently flexible to simulate the bending process. However, the conventional use of the FEM to simulate processes relying on transient local heating proves itself to be extraordinarily costly in terms of calculation time and therefore often impracticable for process planning. So far undertaken approaches to make the simulation faster represent specific solutions for a limited range of process parameters and are not freely transferable. An approximate representation to the transient local heating is provided by the implementation of a semi-static heating load step. It is a very efficient approach, which has barely been researched in terms of the mechanical material response. It is likely, that such approximation strategy particularly used on large numbers of irradiations will even result in a time advantage of several decimal powers. Therefore, the goal of the proposed project is to undertake an adaption of the semi-static heating at the example of the laser beam bending and to assess the boundaries of its effectiveness.

• DFG Programme: Research Grants