To improve the adherence of the oxide scale formed on a γ＇-Ni3Al alloy,a novel Ni3Al fine-grained coating（average grain size： 450 nm） was developed by annealing an electrodeposited Ni-Al composite（average grain size of Ni and Al： 1 um） in a vacuum at 600℃ for 2h.The Ni3Al coating formed from common coarse grains had a homogeneous distribution of fine pores which gave a porosity of 6%.The cyclic oxidation resistance of the coating at 900℃ was greatly increased compared with that of a conventionally coarse-grained Ni3Al alloy（average grain size： 300 um） due to the formation of a continuous and adherent Al2O3 scale.The main reason for the increased scale adhesion lies in that the fine-grained structure improved the strength of the scale/coating interface by preventing the formation of large-sized voids.
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