Phase stability in Ti-V and Ti-Cr alloys: A theoretical investigation

The phase stability of Ti-V and Ti-Cr alloys is examined within the context of an electronic-structure description. Substitutional alloys based on the bcc lattice are considered as well as the complex Laves phases. The relationship between the three Laves phases is examined in detail. Energies of mixing, effective pair interactions, and ultimately phase diagrams are computed and compared with experimental data. A metastable B2 type of structure is predicted in near-equiatomic Ti-Cr alloys, whereas Ti-V alloys exhibit a clear tendency towards phase separation.