Low cost and high efficiency hot-dipped Al-Si coating on DZ125 superalloy improve a better high-temperature anti-oxidation properties.

Si in the outer layer of the coating sets a barrier to O as well as strongly segregating element (Hf, W, Ta) during high-temperature operation.

The second phase SiCr₃ in the inner layer of the Al-Si coating on DZ125 gathers W and Ta.

Formation of the silicon-aluminium-based barrier layer due to different electronegativity of elements Si and Hf as well as Ta.