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Stress Triaxiality in ABAQUS

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GustavSad
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Hi Kumar,

I generally dont use the material models directly from abaqus, I develop some user subroutines and work with them mostly related to sheet metal forming and Ductile fracture using Continuum damage Mechanics.

And my curiosity is why I am not able to use the TRIAX option, I can even generate it from my user subroutine (SDV variable) or the one u said creating new field variables.

Thanks and Regards,

Rohith

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lynx
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 lynx
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Hi Rohiht,

Our research areas are quite similar.

I cant help asking the following,:)

Are you mainly coping with steel or aluminum?

If youre dealing with sheets what sort of yield criteria are you utilizing (Mises, Hill, Barlat, Ghosh,...)?

What is the basis of your finite strain plasticity derivation, hypo- or hyper-elastic plasticity? Or maybe rigid plasticity...

And finally do you cope with anisotropic damage?

Best

Kumar

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GustavSad
Posts: 17
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[QUOTE=Kumar Kurambakurash,5877]Hi Rohiht,

Our research areas are quite similar.

I cant help asking the following,:)

Are you mainly coping with steel or aluminum?

If youre dealing with sheets what sort of yield criteria are you utilizing (Mises, Hill, Barlat, Ghosh,...)?

What is the basis of your finite strain plasticity derivation, hypo- or hyper-elastic plasticity? Or maybe rigid plasticity...

And finally do you cope with anisotropic damage?

Best

Kumar[/QUOTE]

Hi Kumar,

I work with steel and mostly on isotropic materials (MISES). My codes are based on small deformation Hypo elasto plastic formulation. I wont use any large deformation terms like def grad, rotation tensors (R,V,U etc). But I am planing to implement them in future. I studied about anisotropic damage way back, but I am currently using isotropic damage because of its simplicity and easiness in implementation.

Can you tell something about your field..

regards,

Rohith

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lynx
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 lynx
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[QUOTE=unsrohith,5879]Hi Kumar,

I work with steel and mostly on isotropic materials (MISES). My codes are based on small deformation Hypo elasto plastic formulation. I wont use any large deformation terms like def grad, rotation tensors (R,V,U etc). But I am planing to implement them in future. I studied about anisotropic damage way back, but I am currently using isotropic damage because of its simplicity and easiness in implementation.

Can you tell something about your field..

regards,

Rohith[/QUOTE]

Hi Rohiht,

Thanx for the prompt response,

I have developed codes for damage coupled isotropic hyperelastic-plasticity with thermal effects also. I have seperately worked on anisotropic plasticity models (both 3D and plane stress) utilizing hypoelastic plasticity (co-rotational formulations) and written some subroutines which are now tested for industry.

Currently I am after developing anisotropic damage extensions.

Id like to hear details on your damage anisotrpoy approach. Which references are you primarily following within this regard?

Best

Kumar

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GustavSad
Posts: 17
Topic starter
(@GustavSad)
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Joined: 12 years ago

[QUOTE=Kumar Kurambakurash,5880]Hi Rohiht,

Thanx for the prompt response,

I have developed codes for damage coupled isotropic hyperelastic-plasticity with thermal effects also. I have seperately worked on anisotropic plasticity models (both 3D and plane stress) utilizing hypoelastic plasticity (co-rotational formulations) and written some subroutines which are now tested for industry.

Currently I am after developing anisotropic damage extensions.

Id like to hear details on your damage anisotrpoy approach. Which references are you primarily following within this regard?

Best

Kumar[/QUOTE]

Hi Kumar,

Strictly speaking, I havent learned plasticity particularly with names Hypo or Hyper etc. What my prof taught is classical plasticity from HILL with small deformation .I dont know much about hyper elastic based models. I think it involves the large deformation principles R, U and def gradiants Correct me if I am wrong.

The plasticity which I have learned and practicing currently is based on small deformations. And my damage code is coupled to this model.

I just need some references to understand damage coupled isotropic hyperelastic-plasticity with thermal effects ..Can you send me some references u have used to develop the code..

I worked on anisotropic damage formulation involving mixed hardening model 1 year back. I still have the formulation. But I havent code it because of its involvement in more experimental data and complexity.
I followed Prof C. L Chow references a lot...
Still there are lot of unanswered questions in this area like
The condition for critical damage when you say damage is anisotropic etc I feel...
After that I havent updated my knowledge in that area.

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lynx
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On thermo-coupled damage framework there are not much indeed.

I will turn back to this subject in the morning and try to send you mention on some references when I go to the institute tomorrow morning.

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lynx
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 lynx
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Id like to see your derivations for the algorithmic portion regarding Chows approach. I think that once one takes into account anisotropic damage, principal damage values should be utilized in comparison with the damage threshold.

Do you take anisotropic damage rate at the identical eigenvector space of stress rate or plastic strain rate?

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