Ni–Mo–Cr alloy for Interconnect Applications in Intermediate Temperature Solid Oxide Fuel Cells

As part of an effort to develop robust metallic interconnects for intermediate temperature solid oxide fuel cells, a Ni–Mo–Cr alloy is designed, prepared, and investigated in terms of its microstructure, mechanical property, thermal expansion behavior, oxidation resistance, and electrical property. The developed Ni–Mo–Cr alloy possesses a good thermal expansion compatibility with cell components with a coefficient of thermal expansion smaller than at temperature below . Upon oxidation at in air, the oxide scale consisted of two kinds of oxide with densely packed and Cr-free on top of continuous , and intermetallic compound layer is formed underneath the oxide scale. Two stages of parabolic oxidation kinetics are observed with oxidation rate decrease after of oxidation, and good thermal cyclicability of the oxide scale is demonstrated. The area-specific resistance (ASR) as a function of oxidation time shows the similar tendency to the oxidation weight gain, giving an ASR at of for oxidation at in air for and an extrapolated ASR of for oxidation.