Investigation of Electrical Conductivity and Oxidation Behavior of TiC and TiN Based Cermets for SOFC Interconnect Application

Abstract

Titanium carbide and titanium nitride based cermets were produced and investigated to evaluate potential application for SOFC interconnect in terms of electrical conductivity and oxidation resistance. TiC and TiN cermets with 30, 50 and 70 wt% of Ni were fabricated using wet milling and hot pressing, and were then subjected to electrical conductivity measurements in air at 800 ºC for 100 hours. Although all samples tested were slightly oxidized, no degradation has been observed and high electrical conductivity values of the order of 10^3 S/cm have been recorded. The oxide scale strongly adhered to the substrate and protected the sample from further oxidation. With reference to the mixture rules, SEM and EDS results were presented and interpreted to discuss impact of characteristics of the oxide scales on their electrical conductivities.