Two important questions

Does Calculix support adaptive mesh ? I mean changes mesh (refinement) during simulation
It is possible to create Johnson Cook elasto-plastic model and implement in Calculix using MFRONT ?

Check the *REFINE MESH keyword.

The Johnson-Cook model will be available in the next release of CalculiX.

it is available and ready to use,

does “REFINE MESH” keyword works during simulations ?

CalculiX automatically reruns the analysis with refined mesh. Check the description of this keyword in the documentation: