Welding and Heat Treatment with DynaWeld and LS-DYNA

The simulation of welding processes and heat treatments is a challenging task and requires
extensive knowledge and modelling strategies of the underlying processes taking place. For instance, an accurate and predictive modell needs to account for the heat conduction, the changes in the material behavior and the definition of the, in general, complex process itself. DynaWeld together with LS-DYNA assist the stress engineer greatly, such that even complex processes can be efficiently and economically analysed.

DynaWeld is a powerful development environment and preprocessor for LS-DYNA and, in contrast, to the LS-PREPOST preprocessor, is particulary tailored to the needs of welding and heat-treatment simulations. On the one hand, DynaWeld offers a material database, which provides the necessary input data for the simulation.
In addition, it offers the possibility to import data from other programs such as WeldWare, JMATPro or Sysweld.
On the other hand, the software assists the stress engineer in the modelling of clamping fixtures, including their kinematics during clamping and release, as well as the definition of complex welding paths, as they occur in particular when several welding robots are used simultaneously.

LS-DYNA provides the user with a multi-physical solver for the efficient calculation of the underlying thermo-mechanically coupled problem. This is complemented, on the one hand, by the material models *MAT_CWM and *MAT_GENERAL_PHASE_CHANGE, which are especially developed for the welding and the heat-treatment simulation. On the other hand, LS-DYNA allows for the definition of different heat sources for shell and volume elements with energy-input control. As a result, it can be used for an efficient distortion calculation and a detailed residual stress and microstructure analysis for instance.

The aim of the information day is to show the possibilities of welding and heat-treatment simulation with DynaWeld and LS-DYNA, and to give an overview on application possibilities.

Agenda

• Definition of adequate heat sources for the simulation of different welding processes with LS-DYNA
• Exact prediction of weld distortion with LS-DYNA
• Coupling strategies for efficient welding simulation in LS-DYNA
• Simulation-based design of the welded assembly: Start production without scrap and time loss
• Ein neuartiges Materialmodell zur Vorhersage von lokalen mechanischen Eigenschaften aufgrund von Phasenübergängen
• Simulative Festigkeitsbewertgung von Schweißverbindungen
• FabWeld - Komplexe Schweißsimulationsmodelle für LS-DYNA effizient und schnell erstellen

(All presentations by Dr.-Ing Tobias Loose, Loose GmbH and Dr. Thomas Klöppel, DYNAmore GmbH, an Ansys Company).

The info day will take place from 1-5 pm. The lectures are of different lengths and will be held one after the other in consultation with the participants.

Contents

• Welding simulation and its inclusion in process simulations
• Simulation of special welding methods
  • Spot welding
  • Stud welding
  • Friction welding
  • Friction stir welding
  • Induction straightening
• Heat source computation for MSG welding (interface between SimWeld and LS-DYNA)
• Heat treatment and press hardening
• Further developments in LS-DYNA