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Nanocrystallization. an alternative method for improving the high-temperature oxidation resistance of alloys by increasing the supply of the protective oxide-forming element such as Cr or Al has received considerable attention. However, for nanocrystalline (NC) alloy containing two phases, the effect of spatial distribution uniformly of the oxide-forming element oil oxidation has not been studied. In this contribution. three compositionally similar Cu-Ni-Cr NC alloys. with corresponding Cr distribution in atomic, nano-, and micrometer length scale, have been specifically designed and fabricated using direct current magnetron sputtering (DCMS), nanocomposite electrodeposition (NCE). and surface mechanical attrition treatment (SMAT). respectively These NC alloys. In Comparison to the conventional coarse-grained alloy counterpart during oxidation in air in 800 degrees C, exhibited dramatically increased ability to develop a continuous chromia scale, causing, a considerable decrease in the oxidation kinetics. The change in oxidation behavior is associated not only with the small grain size of the alloys. bit( also with the refined distribution of the Cr-rich phases. Among the three methods, microstructures developed by DCMS and NCE were more effective than that front SMAT. The formation of these processing-dependent microstructures and their relationship with the Cr-selective oxidation process are discussed. (C) 2008 The Electrochemical Society. [DOI: 10.1149/1.3049345] All rights reserved.