Thermodynamic Description of the Al-Mo and Al-Fe-Mo Systems

Abstract

The Al-Mo and Al-Fe-Mo systems were critically assessed using the CALPHAD technique. The solution phases (liquid, fcc and bcc) were described by a substitutional solution model. The non-stoichiometric compound AlMo3 was described by a two-sublattice model (Al,Mo)(Al,Mo)3 in the Al-Mo binary system and (Al,Fe,Mo)(Al,Fe,Mo)3 in the Al-Fe-Mo ternary system. Other compounds Al63Mo37, Al8Mo3, Al3Mo, Al4Mo, Al17Mo4, Al22Mo5, Al12Mo and Al5Mo in the Al-Mo system were treated as stoichiometric compounds in the binary system and as line compounds Alm(Fe,Mo)n in the Al-Fe-Mo ternary system. The compounds μ and Fe2Mo in the Fe-Mo system were treated as (Al,Fe)7Fe2(Fe,Mo)4 and (Fe,Mo)2(Al,Mo) in the Al-Fe-Mo system, respectively. Compounds Al5Fe4, Al2Fe, Al5Fe2 and Al13Fe4 in the Al-Fe system were treated as (Al,Fe,Mo), Al2(Fe,Mo), (Al,Fe)5(Al,Fe,Mo)2 and (Fe,Mo)0.235Al0.6275(Al,Va)0.1375 in the Al-Fe-Mo system, respectively. Ternary compounds τ1 and τ2 were treated as Al8(Al,Fe)Mo3 and (Al,Fe,Mo)(Va)3, respectively. A set of self-consistent thermodynamic parameters of the Al-Fe-Mo system was obtained.