FCMAT Stress Strain Data Import

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fred54
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FCMAT Stress Strain Data Import

Post by fred54 »

Hi All - I am new to FreeCAD and was looking at the material cards. I was wondering if there was a hyperfoam material card I could use which I could input known stress strain data curves? Alternatively is there a way to import actual stress-strain data into FreeCad and how?

Thanks!
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bernd
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Re: FCMAT Stress Strain Data Import

Post by bernd »

fred54 wrote: Sun Apr 19, 2020 8:22 pm Alternatively is there a way to import actual stress-strain data into FreeCad and how?
Depends what you would like to use it for?
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bernd
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Re: FCMAT Stress Strain Data Import

Post by bernd »

Related or similar problem. Function dependend material parameter ... https://forum.freecadweb.org/viewtopic.php?f=38&t=32942
fred54
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Re: FCMAT Stress Strain Data Import

Post by fred54 »

Thanks Bernd for your reply!

I want to model a simple foam block and check the behavior of the foam under compression versus actual stress strain data. I think the best way to do this is would be to import the stress strain data. The link you shared shows potential however I am still struggling still on how to create the FCMat. How would I do this to input the stress strain data? Could you send or share an example file of how to input the stress-strain data into the FCMat?

Many thanks in advance!
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bernd
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Re: FCMAT Stress Strain Data Import

Post by bernd »

would you like to use FreeCAD FEM for this?

If yes the stress strain curve behind the first sharp bend is not done in the material cards. This is done in the FreeCAD FEM nonlinear material object.

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fred54
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Re: FCMAT Stress Strain Data Import

Post by fred54 »

Yes, in nonlinear it only allows for three yield points which unfortunately is not truly representative I believe. Can it offer simply more points to match the stress strain curve?
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bernd
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Re: FCMAT Stress Strain Data Import

Post by bernd »

This is because I only need these three ;)
how many do you need?
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