How to find out the elongation with FEA?

[Henry26]

Hello guys,

I'm permforming a FEA in a cast iron part. On the material specsheet has the information "elongation at fracture 15%" how can I find out this value in % on the part with FEA?

Thanks in advance!

 

[rb1957]

stress >>> strain >>> elongation (in fact elongation, as a %age, = strain, no?)

another day in paradise, or is paradise one day closer ?

 

[Henry26]

Yes, I agree with you. So, my FEA got 0.00315 of strain, if specsheet shows 0.15 of strain (15%) at fracture, it means that it won't fracture? Disregard Yield Stress, for the moment.

 

[rb1957]

it would sound like you're well within the fracture strain. if so, you should be well within the material Ftu.

another day in paradise, or is paradise one day closer ?

 

[GregLocock]

You are however beyond the elastic limit for some materials, are you using a non linear material model?

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[Henry26]

Thank you guys, for the answers.

@rb1957
The stress is below to the Ultimate Tensile Strength, but above to the Yield Tensile Strength.

@GregLocock
Yes, non-linear region. I'm performing linear FEA and convert to non-linear stress by Neuber calculation.

I know that this part doesn't broke on field and have infinite life, but when I perform FEA I reach values above to the Yield Stress. I asked to the responsable engineer for this part, and he reached values greater than mine. I believe that if FEA doesn't reach "elongation at fracture 15%" it won't broke, due to be cast iron (GJS-400-15).

See attachment:

http://files.engineering.com/getfil...e-64e7-4fe6-abdf-47bbe8f58166&file=strain.jpg