Thermodynamic modeling of Fe-Ce-Bi system and explanation of interfacial reaction in Fe-45Â at%-Ce/Bi couple

► The Ce--Bi binary system was assessed by the CALPHAD approach. ► Phase relations in the Fe-Ce-Bi ternary system were reasonably extrapolated. ► The reaction path in Fe-45 at%-Ce/Bi diffusion couples at 773 K was determined. ► The formation of CeBi2 in this couple was reasonably explained.