ORIGINAL PAPER Short-Term Oxidation Studies on Nicrofer-6025HT in Air at Elevated Temperatures for Advanced Coal Based Power Plants Vineet V. Joshi • Alan Meier • Jens Darsell • Ponnusamy Nachimuthu • Mark Bowden • K. Scott Weil Received: 26 August 2011 / Revised: 15 January 2013 / Published online: 26 January 2013 Ó Springer Science+Business Media New York 2013 Abstract Several advanced air separation unit (ASU) designs being considered for use in coal gasification rely on the use of solid state mixed ionic and electronic conductors. Nicrofer-6025HT, a nickel-based alloy, has been identified as a potential manifold material to transport the hot gases into the ASUs. In the current study, isothermal oxidation tests were conducted on Nicrofer-6025HT in the tem- perature range of 700–900 °C for up to 24 h. The evolution of oxide scale was evaluated using SEM, XRD, and XPS. The composite surface oxide layer that formed consisted of an outer chromia-rich scale and an inner alumina scale. For the longer times at the higher temperatures evaluated, a NiCr 2 O 4 spinel phase was located at the interface between the alumina and chromia. Based on the experi- mental results a four-step oxidation model was proposed. Keywords Nicrofer-6025HT Á Alloy 602CA Á Oxidation Á XPS Introduction Development of efficient carbon capture technologies for the next generation of coal based thermal power plants, such as integrated gasification and combined cycle (IGCC) and oxy-fuel combustion relies on the supply of high purity oxygen [1–3] Prototype air separation units (ASU) based on the cryogenic separation of gases and Vineet V. Joshi and Alan Meier—Formerly at Kazuo Inamori School of Engineering, Alfred University, Alfred, NY. V. V. Joshi (&) Á J. Darsell Á P. Nachimuthu Á M. Bowden Á K. Scott Weil Pacific Northwest National Laboratory, Richland, WA, USA e-mail: vineet.joshi@pnnl.gov A. Meier Department of Metallurgical and Materials Engineering, Montana Tech, Butte, MT, USA 123 Oxid Met (2013) 79:383–404 DOI 10.1007/s11085-013-9362-6