Work of adhesion of interfaces between M₂AlC (M = Ti, V, Cr) MAX phases and α-Al₂O₃

A fast and generic scheme is proposed to calculate the work of adhesion between two different materials or the cohesive energy between two crystal planes in a material. These calculations make use of the regular solution theory. This theory is extended to describe chemical interactions between atoms at either side of an interface. The so-called regular solution parameter is estimated from thermodynamic values tabulated or solution enthalpies obtained from a macroscopic atom model (MAM). Complex surface definitions at either side of an interface, both in composition and position of atoms, can be dealt with. The proposed scheme has been used to calculate the work of adhesion between M2AlC (M = Ti, V, Cr) type MAX phases and α-Al2O3. Next, the cohesive energy of the MAX-phases and alumina were determined. The cohesion of the M2AlC type MAX-phase is the weakest bond present in the M2AlC- α-Al2O3 systems.