A protective quasicrystalline AlFeCu coating was deposited on TIMETAL 834 substrate by nonreactive magnetron sputtering in order to improve resistance of the alloy to oxidation. Microstructure characterisation of the substrate and the coating was performed by analytical scanning-and transmission electron microscopy as well as X-ray diffractometry. Depending on annealing temperature and time, the deposited coating (2.7 mu m thick) has a different microstructure. The coating in Specimen 1 (annealed 600 degrees C/4 h in vacuum) consisted of two zones: outer, composed of Al5Fe2 and Al2Cu3 phases and inner, in which only quasicrystalline psi phase was present. The coating in Specimen 2 (annealed 600 degrees C/4 h + 700 degrees C/2 h in vacuum) was fully quasicrystalline and consisted of icosahedral psi phase. Both coatings exhibit higher microhardness than the substrate material. It was established that the applied surface treatment essentially improves oxidation resistance of the alloy tested at 750 degrees C during 250 h in static air. Sample weight gain was 60% lower than in the case of uncoated sample. Oxide scale spallation occurred for uncoated alloy while the coated one did not show any spallation. It was found that the very brittle scale formed during oxidation on the uncoated alloy was consisting of TiO2, while that on the coated one consisted mainly of alpha-Al2O3. (C) 2011 Elsevier B. V. All rights reserved.