Effect of Chromium Content on the Oxidation Behavior of Ni-Cr Model Alloys in Superheated Steam

cited By 3International audienceThe present study investigated the oxidation behavior of Ni-xCr model alloys (14 ≤ x ≤ 30 wt pct) in steam at 973 K (700 °C), with particular emphasis on the influence of chromium content. Mirror polishing was employed to reduce the hardened layer, thereby avoiding the synergetic effect with dislocations in the subsurface. To elucidate the oxidation behavior, weight gain measurements and the meticulous characterization of the oxide scale were performed. The optimal Cr content (24 wt pct) corresponded to an oxidation rate slower than the parabolic rate due to the growth of a protective Cr oxide layer. Increasing the Cr content above the optimal amount led to the degradation of oxidation resistance. © 2015, The Minerals, Metals & Materials Society and ASM International