Bi modulus material modeling

The built-in material models can’t handle that, to the best of my knowledge.

So you will have to supply your own material model.

This requires you to;

  • build the necessary libraries and the CalculiX solver on your platform and
  • write a material model in Fortran or C.

These are not typical beginner projects. On the other hand, you will learn a lot by tackling them.

This post might help.

The scripts I use for building CalculiX with the Pastix solver on FreeBSD UNIX can be found here. They will need some changes to work on a typical Linux box. I haven’t built software on a microsoft platform since using Turbo C on MS-DOS, so I cannot offer assistance with that.
If you are on ms-windows, installing msys2 might be a good start.