Development of Oxide Dispersed Ferritic Steel as a Solid Oxide Fuel Cell Interconnect

Abstract

The metallic interconnect is an essential component of the solid oxide fuel cell (SOFC) stack. In this work, the effects of niobium oxide (Nb2O5) added to ferritic stainless steel as a metallic interconnect material for electrical and microstructural properties were studied under SOFC operating conditions. The powders were mixed using ball milling and small pellets with different compositions were fabricated by uniaxial isostatic pressing. Their microstructures were examined by scanning electron microscopy and X-ray diffraction. The electrical properties of the oxide dispersed stainless steel samples were evaluated at high temperature (≥800oC) by measuring the area specific resistance (ASR) for the duration of 1000h. The results showed that the stainless steel sample with 1wt.% Nb2O5 exhibited improved ASR increment value in comparison with the stainless steel sample without Nb2O5.