In this study, sigma(K alpha,beta) production cross-sections, K-beta/K-alpha, KLM/K-alpha and KMM/K-beta RAE intensity ratios of Ni and sigma(K alpha), sigma(K beta 1,2) production cross-sections, K-beta 1,K-3/K-alpha, K-beta 2,K-4/K-alpha, K-beta 2,K-4/K-beta 1,K-3, KLM/K-alpha and KMM/K-beta RAE intensity ratios of Mo have been measured in pure metals and in superalloy specimens. The samples were excited by 59.5 keV gamma-rays from a Am-241 annular radioactive source. K X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The effect of alloying on the fluorescence parameters of Ni and Mo, phase structure, and corrosion behavior were investigated. The X-ray fluorescence parameters of Ni and Mo in superalloys indicate significant differences with respect to the pure metals. These differences are attributed to the reorganization of valence shell electrons and/or charge transfer phenomena in superalloys. (C) 2010 Elsevier B.V. All rights reserved.