elastic-plastic material
elastic-plastic material
(OP)
Hi,
I'd like to use an elastic-plastic material. I define as
-elastic: young modulus and poisson's ratio (217460 N/mm2 and 0,298)
-plastic:yield stress and plastic strain (258N/mm2 and 0)
But I'd like to extract the values as elasto-plastic behaviour so define the gradient of the tangent of the curve in the plastic behaviour. So, to have a linear behaviour until the yield stress and than a gradient of 3% of the young modulus in the plastic part.
How to do?
I tried to define in "plastic">suboptions>rate dependent>hardening>yiel ratio>
Yield stress ratio Eq plastic strain rate
258 0
300 6500 (+/-3% of E)
But it doesn't work!
Thanks a lot,
Nico
I'd like to use an elastic-plastic material. I define as
-elastic: young modulus and poisson's ratio (217460 N/mm2 and 0,298)
-plastic:yield stress and plastic strain (258N/mm2 and 0)
But I'd like to extract the values as elasto-plastic behaviour so define the gradient of the tangent of the curve in the plastic behaviour. So, to have a linear behaviour until the yield stress and than a gradient of 3% of the young modulus in the plastic part.
How to do?
I tried to define in "plastic">suboptions>rate dependent>hardening>yiel ratio>
Yield stress ratio Eq plastic strain rate
258 0
300 6500 (+/-3% of E)
But it doesn't work!
Thanks a lot,
Nico





RE: elastic-plastic material
3% of E is 6523.8 MPa. So yield stress at a plastic strain of 1.0 is 258 + 6523.8 * 1 = 6781.8 MPa
So you need in the .inp file:
*MATERIAL
*ELASTIC
217460.0 , 0.298
*PLASTIC
** yield equiv. plastic strain
258.0 , 0.0
6781.8 , 1.0
Note that 2nd parameter is not equivalent plastic strain *rate", but just equivalent plastic strain.
MRG
p.s. You have asked a lot of questions in this forum recently. It would be nice if you thanked those who have helped you
RE: elastic-plastic material
I can thank a lot to all people who answered to my questions. You know, I begin to use Abaqus and try to do it alone is very difficult! So, it is impossible for me to answer to the different questions. But in a few weeks, it would be possible!
and thanks to you, MRG!!!
RE: elastic-plastic material
I think what MRG really meant by thanking people is awarding them a star with the "Thank ******** for this valuable post!" clickable text under everyones post!
RE: elastic-plastic material
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RE: elastic-plastic material
It's just that Nicolas has been particularly demanding of the board, particularly in posing the questions at times! But that is perhaps a cultural issue. I just wanted to point out that the effort people put in is all for free. It is nice to receive a thank you.
Actually, what I dislike the most are newcomers who ask a question, then never let us know how they get on when they receive replies.
RE: elastic-plastic material
It is entirely my fault. Stop this new posts about that problem. I neglected this point of thanks with stars. I just thanked in my questions. I learned something and I thank you a lot for this. I won't forget it in future. This forum helped me a lot in my work and answered to a lot of my questions. I understand that people like to receive a thank you, that's normal!
So, mea culpa!
nico
PS:I don't think that this forum is a good place to some "special"(cutlural) problems. If people make a mistake, it is fine to signal it and people are sufficiency civilized and grateful to understand and react about it!
"This site works the best when conversations are kept on a technical level. Thank you."