Oxidation Behavior and Electrical Properties of NiO- and Cr₂O₃- Forming Alloys for Solid Oxide Fuel Cell Interconnects.

Journal Article · Sun Jan 01 04:00:00 EST 2006 · Oxidation of Metals

DOI:https://doi.org/10.1007/s11085-006-9018-x· OSTI ID:931614

Brady, Michael P ^[1]; Pint, Bruce A ^[1]; Lu, Z G ^[2]; Zhu, Jiahong ^[1]; Milliken, C ^[3]; kreidler, E ^[3]; Miller, Leslie S ^[1]; Armstrong, Timothy R. ^[1]; Walker, Larry R ^[1]

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1. ORNL
2. Tennessee Technological University
3. TMI Inc

The goal of this paper was to determine if NiO-forming alloys are a viable alternative to Cr{sub 2}O{sub 3}-forming alloys for solid-oxide fuel-cell (SOFC) metallic interconnects. The oxide-scale growth kinetics and electrical properties of a series of Li- and Y{sub 2}O{sub 3}-alloyed, NiO-forming Ni-base alloys and La-, Mn-, and Ti-alloyed Fe-18Cr-9W and Fe-25Cr base ferritic Cr{sub 2}O{sub 3}-forming alloys were evaluated. The addition of Y{sub 2}O{sub 3} and Li reduced the NiO scale growth rate and increased its electrical conductivity. The area-specific-resistance (ASR) values were comparable to those of the best (lowest ASR) ferritic alloys examined. Oxidation of the ferritic alloys at 800 C in air and air+10% H{sub 2}O (water vapor) indicated that Mn additions resulted in faster oxidation kinetics/thicker oxide scales, but also lower oxide scale ASRs. Relative in-cell performance in model SOFC stacks operated at 850 C indicated a 60-80% reduction in ASR by Ni+Y{sub 2}O{sub 3}, Ni+Y{sub 2}O{sub 3}, Li, and Fe-25Cr+La,Mn,Ti interconnects over those made from a baseline, commercial Cr{sub 2}O{sub 3}-forming alloy. Collectively, these results indicate that NiO-forming alloys show potential for use as metallic interconnects.

• Research Organization: Oak Ridge National Laboratory (ORNL); Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: FE USDOE - Office of Fossil Energy (FE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 931614
• Journal Information: Oxidation of Metals, Journal Name: Oxidation of Metals Journal Issue: 3/4 Vol. 65; ISSN OXMEAF; ISSN 0030-770X
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
AIR
ALLOYS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
KINETICS
OXIDATION
OXIDES
PERFORMANCE
SOLID OXIDE FUEL CELLS
WATER