National Physical Laboratory

MTDATA SGTE Nuclear Database

The SGTE Nuclear Database has been developed and maintained on behalf of SGTE by ThermoData. It is designed for in vessel applications to allow calculations of the thermochemical equilibrium state at any step in a severe nuclear accident in order to improve the predictions of thermo-hydraulic or other accidents codes. Possible calculations include:

  • condensed state phase diagrams, phase transitions, liquidus/solidus equilibria, compositions and proportions of phases,
  • thermodynamic calculations coupled to thermo-hydraulic, viscosity, segregation, residual power distribution,
  • gaseous fission products release for a variety of external conditions

The database covers the following system:

O-U-Zr-Fe-Cr-Ni with the addition of Ar and H

and includes the 6 component oxide system:


although the database cover the entire range of composition from metal to metal oxide.

The Gibbs energies of all possible condensed or gaseous substances and solution phases were critically assessed by means of the CALPHAD sophisticated optimisation procedure, using all the selected experimental information. Care has been taken in constructing the database to ensure that it is self-consistent and that all the available experimental information is satisfactorily reproduced.

Further information can be obtained by clicking here.