Changing material properties between steps

[MK1966]

Dear All,

I use Abaqus 6.10. to perform two different analyses with 5 steps. In the first analysis material properties (elastic+plastic+creep)remain the same in all steps. However, in the second one the effect of material plasticity should be ignored after 3rd step. How can I do this change of material properties in the second analysis? I suppose that it is necessary to apply field variable. However, I did not know to do this. Any help will be highly appreciated. Here are material properties:

*Material, name=Material-1
*Creep
5e-16,5.,0.
*Elastic
210000., 0.3
*Plastic
400., 0.
425., 0.01
450., 0.05
475., 0.09
500., 0.13
525., 0.18
550., 0.23
600., 0.4
650., 0.49
700., 0.57

Regards

 

[Mustaine3]

You cannot deactivate the plasticity with field variable, but maybe you can define the yield stress high enough, so the behavior will be elastic again. But the existing plastic strains won't disappear. I'm not sure if that would converge.

Working with field variables is not difficult. Make you material dependent of one (can be done in /CAE) and then add *Field with reference to an amplitude to define when you want to have what value of the field variable.
Request FV as Field Output to see the value of the field variable in postprocessing.

See Abaqus Analysis Users Guide 34.6.1 Predefined fields

 

[MK1966]

Thank you for helpful tips. First 3 steps are static analysis in which creep is ignored. What do you think about idea that the material is considered as two different materials. First elastic-plastic material would be applied in the first 3 steps. In the next two steps it would be used the second material with elastic-creep properties. What do you feel is it possible to consider this so? If yes, may I use field variables to modify the existing input file and how it should be done?

 

[Mustaine3]

You cannot exchange the referenced material of an element during the analysis.

An option may be, that you create a new analysis and map the existing results. See keyword *Map Solution.

 

[MK1966]

The problem is solved. Thank you for your kind support. Regards