Electron theoretical investigation of the stability of the B2-TiFe compound

The metastable phase diagram of the BCC-based ordering equilibria in the Ti–Fe system has been calculated using a truncated cluster expansion, through the combination of FP-LAPW and cluster variation method (CVM) in the irregular tetrahedron cluster approximation. The results are compared with phenomenological CVM assessments of the system and suggest that the value for the experimental formation enthalpy of the B2-TiFe compound should be significantly more negative than the currently assessed value.