The thermal and physical properties of B2 Al-Ir-X (X = Ni, Ru, Pd, Co, Fe) alloys are presented for the whole B2 field of each ternary system. Using the BFS method for alloys, the phase structure, long and short range ordering behavior and the site preference trends for X additions to AlIr are discussed, and results are shown for the cohesive energy, equilibrium lattice parameter, bulk modulus, coefficient of thermal expansion, heat capacity, and melting temperature for the five ternary systems in the B2 field.