type: Hooke
references:
  - T. Maiti and P. Eisenlohr,
    Scripta Materialia 145:37-40, 2018,
    https://doi.org/10.1016/j.scriptamat.2017.09.047
C_11: 1.e+8
C_12: 1.e+6
C_44: 4.95e+7