Learning Forum

[Benhour Amirian]

Hello everyone,

I was wondering if you could help me how to import stress strain curve for material definition in dyna. I am trying to use that for defining composite material.

Thanks.

[Reno Genest]

Hello Benhour,

Which material model are you using? Which software are you using to create the model?

 

Reno.

[Benhour Amirian]

Hi Reno,

Thanks for your reply. I am new to LS-Dyna.

I am using LS-Prepost for creating the model and I need to simulate a simple 2D model under uniaxial tensile loading. Suppose that I am using a linear elastic model.

Bests,

Benhour

[Reno Genest]

Hello Benhour,

If you are using a linear elastic model (*MAT_001 in LS-DYNA), you don't need stress-strain curves. Only density, young's modulus, and Poisson's ratio.

Importing a stress-strain curve makes sense for a material model with plasticity such as *MAT_024 (for modelling metals).

 

Reno.

 

[Benhour Amirian]

Thanks Reno for your quick response.

Actually, I need to mdel a single element composite matrial, which I believe I need to use MAT_052. Besides, suppose that I am creating a model for MAT_024. What is the approach for importing the stress-strain curve?

I appreciate your help.

 

Benhour

[Andreas Koutras]

Hello,

Are you referring to MAT_054, which is a popular material for modeling composites? MAT_054 does not support direct use of stress-strain data. Instead you can determine the material constants based on your data.

In MAT_024, LCSS is used to define stress-strain data in terms of effective stress -vs- effective plastic strain. When LCSS references a load curve, the curve of the stress-strain data is defined with *DEFINE_CURVE. Further details are shown in the section of MAT_024 in Manual Vol II https://lsdyna.ansys.com/manuals/

Some examples are available here:

https://www.dynaexamples.com/

https://www.dynaexamples.com/introduction/intro-by-j.-day/misc/mat24-table

https://www.dynaexamples.com/introduction/process_simulation