Mechanical APDL Basic Analysis Guide - Ansys

You can save linear material properties (whether they are temperature-dependent or constant) to a file or
restore them from a text file. (See Using Material Library Files (p. 15) for a discussion of material library files.)
You also can use CDWRITE,MAT to write both linear and nonlinear material properties to a file.
Note
If you are using the CDWRITE command in any of the ANSYS-derived products (ANSYS Emag,
ANSYS Professional, etc.), you must edit the Jobname.CDB file that CDWRITE creates to remove
commands which are not available in the derived product. You must do this before reading the
Jobname.CDB file.
1.1.4.2. Nonlinear Material Properties
Nonlinear material properties are usually tabular data, such as plasticity data (stress-strain curves for different
hardening laws), magnetic field data (B-H curves), creep data, swelling data, hyperelastic material data, etc.
The first step in defining a nonlinear material property is to activate a data table using the TB command
(see Material Model Interface (p. 8) for the GUI equivalent). For example, TB,BH,2 activates the B-H table for
material reference number 2.
To enter the tabular data, use the TBPT command. For example, the following commands define a B-H curve:
TBPT,DEFI,150,.21
TBPT,DEFI,300,.55
TBPT,DEFI,460,.80
TBPT,DEFI,640,.95
TBPT,DEFI,720,1.0
TBPT,DEFI,890,1.1
TBPT,DEFI,1020,1.15
TBPT,DEFI,1280,1.25
TBPT,DEFI,1900,1.4
You can verify the data table through displays and listings using the TBPLOT or TBLIST commands.
Figure 1.2 (p. 7) shows a sample TBPLOT (of the B-H curve defined above):
Figure 1.2 Sample TBPLOT Display
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1.1.4. Defining Material Properties
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