How to track surface impurities during extrusion?

NarendraSingh

Billet surface is typically oxidized and contains impurities. During extrusion these impurities enter the profile. In direct extrusion, this oxidized layer and other surface impurities segregate at the back end of the billet and enter the profile at the end of extrusion cycle. In the case of indirect extrusion, these enter the profile during the entire extrusion process.

 

 

 

 

 

NarendraSingh

HyperXtrude tutorial number HX-0303 explains the steps involved in simulating the migration of billet skin during extrusion.

 

Tips:

 

1. Define a skin - 2 to 3 layers of elements on the billet outer surface. These skin elements must be stored in a separate component (say Billet_Skin_3D). The thickness of this skin layer should not be more than 3 mm. These elements represent layer with surface impurities.
2. In the TCL file,
3. Set analysis type to TransientMovingBoundary
4. Define skin component (SetBilletSkin Sin3D)
5. Activite skin tracking flag (pset BilletSkinTracking on)
6. Define SolidFluidInterface condition at the back end of the billet (where the ram/dummy block touches billet). Specify velocity condition in the extrusion direction and zero traction for others.
7. Specify smaller time steps at the beginning of extrusion cycle.
8. Set NonLinearTolerance to 0.005 to reduce CPU time.
9. Movement of billet skin interface is stored in H3D file.