Answer:
After setting a material to user-defined, the definition type can be changed; this controls how the modulus of elasticity, shear modulus, and Poisson's ratio are related to each other. There are three options in the drop-down menu.
1. E | G | (v)
This option calculates Poisson's ratio based on G and E.
2. E | (G) | v
This option calculates G based on E and Poisson's ratio.
3. E | G | v
This option keeps all properties independent of each other. This option is best to choose if you want the properties to be independent.
This is a good solution if this error message appears:
"The relation e=2G(1+v) is not fulfilled. The material cannot be assigned to a surface or solid without satisfying the relation. Please adjust the material parameters."
Making all of the material properties independent of each other will fix this error.
