The materials selections of MoSi
2/Mo/Nb/
γ – TiAl FGMs were performed with the analysis of FGMs database. The stable FGMs criterion without interlayer cracking of ∆
α∆
T less than 4.3 × 10
−3 was derived from FGMs database, where ∆
T is the differences in the thermal expansion coefficient and temperature ∆
T is between processing and room temperatures. The MoSi
2/Mo/Nb/
γ – TiAl FGMs were prepared using the spark plasma sintering (SPS) method, followed by siliconized in molten salts. Nb foil was firmly joined to the
γ – TiAl surface and Mo foil was firmly joined to the Nb foil. The ∆
αNb−Mo∆
T and ∆
αγ−TiAl−Nb∆
T values were consistent with the criterion, where ∆
αNb−Mo, ∆
αγ−TiAl−Nb, and ∆
T arethe differences between the coefficients of thermal expansion of Nb and Mo, and of
γ – TiAl and Nb, and ∆
T is the difference between the SPS temperature and room temperature. The MoSi
2/Mo/Nb/
γ – TiAl FGMs were dense and had neither cracks nor voids. The thickness loss of the MoSi
2/Mo/Nb/
γ – TiAl FGMs was 11
µm after 200 h exposure to air at 1323 K.
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