SPRINGBACK

The QS/Springback GUI (as shown in Figure 8.3.1) allows the user to easily setup a springback analysis.

Figure 8.3.1 The QS Springback GUI.

Tool definition GUI

Allows the user to define deformed blank. Selecting the TRIM BLANK button carries out the trim operation. The user has to read in the trim curve. By default, Blank will be assigned automatically after the deformed blank (in DYNAIN format) is read into the eta/DYNAFORM database.

Blank Parameters

Defines blank material and properties.

Control

The user can either select the single or multi step implicit method. The single step implicit method is the default setting. If it does not provide converged springback results, the user can select the multi-step implicit method for the springback analysis.

The coarsen control can be activated to combine the refined mesh prior to springback analysis. The function allows the eta/DYNAFORM solver to combine neighbouring elements that have an angle of less than a certain degree (default is 8 degrees). Coarsening blank mesh can reduce computational noise, and therefore helps the springback model to converge.

Constraint

Enables the user to select proper clamp points to prevent rigid body motion during springback analysis.

Implicit Parameters

Defines parameters for springback analysis. The dialog window is shown in Figure 8.3.2. For detailed information about each parameter, refer to LS-DYNA User's Manual.

Figure 8.3.2 The Implicit Parameters dialog window.