Permanent set

[maheshh]

I have a supported sheet metal structure (like a spring) which is deflected by a certain amount, and then relaxed. I am expecting to see some permanent set, but it seems either my property specs are not right, or I am making some mistake setting up the analysis.
As for properties, for the sheet metal component, I am specifying Y, Poisson's ratio, yield strength and tangent modulus.
I have another dummy steel component, which presses (displacement BC) against the "spring" component to cause the deflection, and then returns to the original position.
Once the dummy component returns to the original position, I am expecting the contact to open up creating a gap because of the permanent set. But it does not seem to be that way.

Am using Workbench environment.

Thanks in advance.

 

[SFLM]

Maheshh,

I am not 100% sure I got your point, but I did not see any plasticity model in your problem description. If you don't use plasticity, you should not expect permanent deformation.

Steve

 

[maheshh]

I thought if I include yield and tangent modulus, in case the stresses exceed yield strength of the material, there will be some permanent deformation. Maybe I am mistaken. I will read up more about it.

Thanks.

 

[Drej]

You don't give enough information in your post - which elements are you using?

Make sure you are using elements that allow for plastic behaviour (go to the element page in the manual and look at the description: e.g. SHELL63 is an elastic shell and will not allow for plastic deformation).


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[SFLM]

Maheshh,

You are using ANSYS WB. So, you don't have to care about element type which is automatically chosen by the program. What you said doesn't work like that. You need to define a plasticity model and apply the properties in order the see any permanent deformation of whatever you are simulating.

I hope it helped.