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Abstract. Lower density materials of TiAl based intermetallic alloys have recently attracted intensive attention for the replacement of nickel-based superalloys used at high temperatures. As aluminium-rich titanium aluminide intermetallic compounds are normally brittle, two-phase α 2 -Ti 3 Al/γ-TiAl alloys have been developed. To increase the corrosion resistance of these alloy systems, an aluminide coating of TiAl 3 layer is normally applied. During operation at high temperatures, however, interdiffusion between the coating and the alloy substrate can occur and decrease the TiAl 3 layer thickness of the coating. The effects of temperature exposure on the growth of the TiAl 2 interdiffusion zone layer on two-phase α 2 -Ti 3 Al/γ-TiAl alloys with a chemical composition of Ti-47Al-2Nb-2Cr-0.5Y-0.5Zr are presented in this paper. The exponents for kinetics and rate constant of the TiAl2 interdiffusion layer growth of this multi-component system were found under variation of temperature. The results were compared with those from other researchers.