Tillotson equation

The Tillotson equation (or Tillotson equation of state or Tillotson EoS) is an equation of state (relating pressure, volume, and temperature) for the shock of very high speed impacts of metals (metals in the "chemistry" sense, e.g., iron). It is an equation-form that includes heuristic parameters intended to capture the relevant characteristics of the material, in particular, those associated with the material's melting and/or vaporization. Planetary science uses the equation in some models of impacts within the solar system.