Learning Forum

[shahria]

Hello everyone,

 

I am working on a simple explicit model that contains only a cubic body in tension. I used the 4 node tetrahedral mesh (ELFORM=10) and MAT_ELASTIC material model with the default time step control settings. However, when I plotted the Stress-Strain curve from the Force and Displacement values of the model, the curve appeared to be nonlinear. After a closer look at the documentation I found out that MAT_ELASTIC is hypoelastic material model, which might be the reason for this non linear elastic behaviour. Can anyone please suggest a way to achieve linear elastic material behavior in Ls Dyna Explicit? I am having a hard time finding any.

 

Thanks,

Shahriar.

 

 

 

 

[Pedram Samadian]

Hi Shahria,

It has nothing to do with the hypoelasticity of the material model. Have you tried other element types? 1-point tetrahedral solid elements (Type = 10) are not recommended for general metal forming applications. I developed a cube tensile model with *MAT_ELASTIC and Element Type 1 and got a linear load-displacement response. Similar results are obtained using common element types of -1 and -2. 

Thanks,

Pedram