1117
Oxidation Characteristics of Nano-Oxide Dispersed Ferritic Stainless Steel Alloys for Solid Oxide Fuel Cell Interconnects

Monday, 14 May 2018
Ballroom 6ABC (Washington State Convention Center)
M. T. Mehran, R. H. Song, T. H. Lim, S. B. Lee, and J. E. Hong (Korea Institute of Energy Research (KIER))
Ferritic stainless steel based metallic interconnects for intermediate temperature solid oxide fuel cells (SOFC) show performance degradation due to the continuous growth of chromia scale. Modification of stainless steel alloy is considered to be one of the viable options to utilize ferritic stainless steel for long-term application in SOFC as interconnect. In this study, we developed the nano-oxide dispersed alloys of ferritic stainless steel SUS430 and studied the oxidation properties at 800 °C in oxidizing conditions. Nano-oxides of CeO2, La2O3, Y2O3, and LaCrO3 were dispersed in commercial SUS430 by high-energy ball milling and the specimen were fabricated by uniaxial and isostatic pressing and sintering in H2 at 1400 °C. The sintered samples were tested for oxidation properties and long-term area specific resistance (ASR) in the air at 800 °C for 1000h and post-test SEM and XRD analysis was performed to analyze the oxide scale. It was found that the addition of up to 3wt. % nano-CeO2 is the most beneficial among the added nano-oxides in order to improve the oxidation properties of SUS430 due to the reduced thickness of the chromia scale, and improved adhesion of the oxide scale and the alloy substrate.