And as for solvent vs solute in a binary alloy, the metal with higher concentration is solvent, lower concentration is solute. If you can read a phase diagram you can find it yourself!
Just for starters, there are seven solids here- α,β, β',γ, δ, ε, η
@Sumit Bhowmick sir, can you suggest me any specific book regarding the topic? I want know the crystal structures of different phases in a copper zinc phase diagram in details. Specially the intermediate phases. Thank you.