Large Deformation Vs Small Deformation (Nlgeom on Vs off)
Large Deformation Vs Small Deformation (Nlgeom on Vs off)
(OP)
Hi
I am simulating simple uniaxial tensile test using Standard (Implicit) Abaqus.
Material (Density elasticity and plasticity) has been defined.
Everything is just fine.
The problem is when I turn the Nlgeom on, it show necking.
What is the theory behind this?
And how can Abaqus triger necking at certain time?
Anyone can help me...I looked into the documentation but could not find a lot.
Thank you.
I am simulating simple uniaxial tensile test using Standard (Implicit) Abaqus.
Material (Density elasticity and plasticity) has been defined.
Everything is just fine.
The problem is when I turn the Nlgeom on, it show necking.
What is the theory behind this?
And how can Abaqus triger necking at certain time?
Anyone can help me...I looked into the documentation but could not find a lot.
Thank you.





RE: Large Deformation Vs Small Deformation (Nlgeom on Vs off)
Decrease the force to a point that the material should not be yielding and there will be no plastic deformation (and no necking).
RE: Large Deformation Vs Small Deformation (Nlgeom on Vs off)
I forget to tell it is steel.
The material yield and plastic deformation starts.
This is good. But the issue is necking occure only when Nlgeom option is On.
I artificially increase the fracture strain from 0.11 and True stress of 1200MPa to fracture strain of 5 (or 500%) and true fracture stress of 1400MPa and still necking occure.
Why? and What is the theory behind this?
RE: Large Deformation Vs Small Deformation (Nlgeom on Vs off)
Brian
www.espcomposites.com