Pressing out a brass part

I am trying to model punching out a pressed brass fixing through a aperture (die).
I am expecting the thinner upper section of the brass to deform in preference to the thicker inner lower section allowing it to be pushed through the die. My aim is to understand the force I need to push the fixing through and to balance the sizes/thicknesses of the inner and outer sections so this happens rather than jamming up or rupturing.

At first I was experiencing singularities that we stopping the simulation but now it fails with a error that is very difficult to see what is wrong. It sounds like if may be a software issue:
" ------! ! <A><JEVEUX_08>! ! ! !

The GLOBALE base was created with version 0.00.00! ! and you use version 14.02.00! ! ! !

Council:! ! In general, the base can only be used with the version of the code that built it,! ! catalogs of items are stored in the base when it is created, and some of the structures! ! based on their description, which may vary from version to version. ! ! ! ! ! ! This is an alarm. If you don’t understand the meaning of this! ! alarm, you can get unexpected results! ! !-------------------------------------------------------------------------------------------------------! !-------------------------------------------------------! ! <EXCEPTION><DVP_2>! ! ! ! Digital error (floating point exception). ! ! ! ! ! ! ! ! There is probably an error in the programming. ! ! Please contact your technical assistance. ! !-------------------------------------------------------! … __stg1_txt5 # ------------------------------------------------------------------------------------------ Order No: 0001 Type Concept"

This is the project:

There is an earlier version that never got past the singularity issue (perhaps not detailed enough)

this is based on the project:

I need help understanding if I am using the completely wrong simulation type or if not where I am needing to alter the setting to get this working.

Many thanks


I will check this out and get back to you ASAP! Tagging the @fea_squad in the meantime.




You must stabilize the ‘pressing’ body. Leaving the body motion constraint only to the contacts leads to divergence.

For that, you can add an ‘Elastic support’ to a face of the ‘pressing’ body. Try that and see if it helps with convergence.

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To all, thanks for looking at this for me. Support have been great and one big issue was the contact setting. By default the parts are ‘Bonded’ therefore they will not slide against each other. By deleting the contact settings (I am still not clear how this gets deleted) so that it says “Contacts (0)” we can free them up to move. The other issue was mesh density to eliminate singularities (unrealistic stress concentrations).
Also having a s-n curve for the ‘plastic’ profile seem to help. Note first step needs to be the yield strength or higher I understand. Any advice on sources for reliable s-n curves would be helpful, without having a tensile testing machine handy it seems to be elusive.

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Hi! Glad to be able to help.

To correct your confusion: you are not looking for a S-N curve (that is for fatigue life assessment), but instead for a Stress-Strain curve.

For steels (or general ductile) materials you can use test data, or build a curve from specified yield and ultimate strengths, using models such as Ramberg-Osgood or bi-linear plasticity (search for that on the web, you will find lots of resources). Keep always present that you should be using real stress and strain values (as opposed to engineering values).