Microstructural variation in sputtered Ni 9 7Cr 5 5Al 7Ti (wt%) nanocrystalline coatings during high temperature oxidation was observed. The formation of TiO 2 on sputtered Ni Cr Al Ti coatings (or the sputtered coatings removed oxide coating after 90 min oxidation) have been investigated. It was found that the formation and TiO 2 of growth are closely related to the pricipitation of Ni 3(AlTi) phase. These effects are also discussed in detail