type: thermalexpansion
references:
  - https://commons.wikimedia.org/wiki/File:Coefficient_dilatation_lineique_aciers.svg,
    fitted from image description (Scilab code)
A_11: 12.70371e-6
A_11,T: 7.54e-9
A_11,T^2: -1.0e-11
T_ref: 273.0