Recent Developments in LS-DYNA to close the Virtual Process Chain for Forming, Press Hardening and Welding

Thomas Klöppel; Andrea Erhart; André Haufe; Tobias Loose

doi:10.4028/www.scientific.net/KEM.651-653.1312

Paper Titles

Separated Representations of Incremental Elastoplastic Simulations
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Efficient Updated-Lagrangian Simulations in Forming Processes
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Numerical Damage and Failure Modelling of Lightweight Alloys during Metal Forming Processes
p.1301

Study of Formability of Sandwich Shells with Metal Foam Cores Based on Punch Penetration Test
p.1307

Recent Developments in LS-DYNA to close the Virtual Process Chain for Forming, Press Hardening and Welding
p.1312

Agile Multiscale Modelling of the Thermo-Mechanical Processing of an Aluminium Alloy
p.1319

Virtual Joining Factory – Integration of Microstructure Evolution in the Manufacturing Process Chain Simulation
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Simulation of Incremental Forming Processes Using a Thermo-Mechanical Partitioned Algorithm
p.1331

Identification Problem of Internal Variables Model of Material
p.1339

HomeKey Engineering MaterialsKey Engineering Materials Vols. 651-653Recent Developments in LS-DYNA to close the...

Recent Developments in LS-DYNA to close the Virtual Process Chain for Forming, Press Hardening and Welding

Abstract:

Forming, press hardening and welding are a well-established production processes in manufacturing industry, but predicting the finished geometry and the final material properties of the processed parts is still a major issue. In particular, deformations caused by welding are often neglected in the virtual process chain, although they have to be compensated for in order to fulfill the requirements on shape tolerance. This presentation will give an overview on novel features of LS-DYNA implemented particularly for welding simulations.To begin with, new keywords will be presented that allow applying the heat generated by the weld torch. LS-DYNA offers a very convenient way to define the well-known Goldak heat source, but it is also possible to define arbitrarily shaped torch geometries.In order to obtain a predictive model for welding simulations, specific material models have been devised in LS-DYNA. The properties of filler material in weld seams are accounted for by a ghost material approach. Material is initialized as ghost material and is activated, i.e. it is given base material properties, when the temperature reaches the melting point. This approach has been implemented for a relatively simple thermo-elasto-plastic material formulation *MAT_CWM as well as for the more complex material law *MAT_UHS_STEEL. The latter has initially been implemented for press hardening simulations and is able to predict the microstructure of steel alloys including phase transformations and the resulting mechanical properties.In this contribution, details of the material formulations and novel features are presented. Examples will demonstrate how these features can be applied to multistage processes including several forming and welding stages.

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Periodical:

Key Engineering Materials (Volumes 651-653)

Pages:

1312-1318

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.651-653.1312

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Online since:

July 2015

Authors:

Thomas Klöppel*, Andrea Erhart, André Haufe, Tobias Loose

Keywords:

Forming Simulation, Press Hardening Simulation, Virtual Process Chain, Welding Simulation

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* - Corresponding Author

References

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