type: Hooke

references:
  - Z. Wang et al.,
    Materials Science and Engineering:A 674:406-412, 2016,
    https://doi.org/10.1016/j.msea.2016.08.010,
    fit to Tab. 2 (last 3 rows)

C_11: 243.9e+9
C_11,T: -5.410e+7

C_12: 157.0e+9
C_12,T: -9.352e+6

C_44: 117.9e+9
C_44,T: -2.798e+7

T_ref: 293.15