Material Law 12

Gokul Ramarathnam_20422

Hello,

 

I'm in the early stages of orthotropic material modeling using Law12. This is new to me, so I am trying to verify that the material law works for a simple isotropic coupon. I gave identical properties for all directions and identical values for yield. I am not sure how to get the values of B 'material hardening parameter' and n 'material hardening exponent'. Could you offer me some assistance regarding this? Also, can Law12 capture the plasticity that we see in say a simple Aluminum stress strain curve? I believe that B and n drive the non linearity but I am not sure how to effect that into the curve.

 

Appreciate your help. 

 

Thank you!

Pranav Hari

Hi Gokul Ramarathnam

 

Law 12 describes a solid material using the Tsai-Wu formulation that is usually used to model composites. This material is assumed to be 3D orthotropic-elastic before the Tsai-Wu criterion is reached.

Altair Forum User said:

This is new to me, so I am trying to verify that the material law works for a simple isotropic coupon. I gave identical properties for all directions and identical values for yield. I am not sure how to get the values of B 'material hardening parameter' and n 'material hardening exponent'.

 

The strain hardening exponent (n)and strain hardening parameter(B) is a material's constant which is used in calculations for stress- strain behavior in strain hardening

If you are having an isotropic property then a suggested workaround is that you can run an analysis using Material law 2 with the value of iflag=1. Then you will get the values of 'B' and 'n' as the output of the results. This values can be used as the input for Material law 12

 

 

Thanks

 

 

Gokul Ramarathnam_20422

Hello Pranav,

 

Thank you for getting back to me on this. I will try starting with Law2.

Cheers.