How to include a non-linear material model ?

Altair Forum User

I have the stress - strain values at discrete data points from uni- tensile test. How too include that in Hypermesh while defining material properties ?

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Altair Forum User

Hi Ahilan,

 

The stress-strain curve should be defined using TABLES1 card and MATS1 cards.

Rahul_P1

1.

In the Tab area, click on the Utility menu. If not active, click View > Utility.

2.

Click on the TABLE Create tool.

3.

Click on Create/Edit Table and select the table type as TABLES1.

4.

Click Next.

5.

Click the radio button for Create New Table and enter the Name of the table.

6.

Next, populate the X and Y fields of the table, as shown below.

7.

Click Apply.

A dialog box will appear which says 'The load collector with TABLES1 card image is created’.

8.

Click OK to close the dialog box.

Now, the elasto-plastic material needs to be updated.

9.

In the toolbar, click the Material icon .

10.

Toggle the Update subpanel.

11.

Click on mats and select the previously created material mats1.

12.

Click update/edit.

13.

Click on MATS1 to define the elastic-plastic material for NLSTAT analysis.

14.

Click TID and select stress-strain.

Altair Forum User

Altair Forum User said:

 

1. In the Tab area, click on the Utility menu. If not active, click View > Utility.

2. Click on the TABLE Create tool.

3. Click on Create/Edit Table and select the table type as TABLES1.

4. Click Next.

5. Click the radio button for Create New Table and enter the Name of the table.

6. Next, populate the X and Y fields of the table, as shown below.

7. Click Apply.

A dialog box will appear which says 'The load collector with TABLES1 card image is created’.

8. Click OK to close the dialog box.

Now, the elasto-plastic material needs to be updated.

9. In the toolbar, click the Material icon .

10. Toggle the Update subpanel.

11. Click on mats and select the previously created material mats1.

12. Click update/edit.

13. Click on MATS1 to define the elastic-plastic material for NLSTAT analysis.

14. Click TID and select stress-strain.

 

 

Please also tell how can we add temperature dependent specific heat values. The above process is for stress strain curve but following same procedure in specific heat or thermal conductivity I am not able to assign the values. I am using optistruct in Hyperworks 12. 

Rahul_P1

shanky456

 

This is implemented in Optistruct 13.0 (to be released next) in the MAT4 and MATT4 cards.

Altair Forum User

Is it possible to given the same stress - strain data as symbolic expression ? 

 

https://drive.google.com/file/d/0B2rIYPnVjYNEdkVlM0h6WHJNeWs/view?usp=sharing

Altair Forum User

Hi,

 

I don't see a way to write expression for stress and strain in HyperMesh.

 

as a workaround you can write the same expression in an excel sheet and input the values of the parameters in the expression.

 

Now, you can import the excel sheet while creating TABLES1 card. (to import .csv file goto Utility browser>>Tools>>Import table>> TABLES1>>select the .csv file)

Altair Forum User

Hello....Could anyone help me here

 

Why do I get this error when I am trying to introduce an elasto plastic material using the process explained.

 

 There were 2 error messages during input processing.
  The first message is repeated below:

  *** See next message about line 368808 from file:
      C:/Temp/Tank/KW 32/Dienstag/09.08_Elasto Plastic material_Gummi/09.08_Elasto_Plastic_Material_G
   'SURF          69ELFACE'
  Syntax error(s) found in bulk data 'SURF' Card.

 

Regards

 

Altair Forum User

Hi User,

Do you have any contact surface in your model?..