The effect of Cr2O3 scale on electrical conductivity of Cobalt-spinel-coated ferritic stainless steel

One of the most effective approaches to improve the interconnect properties
is to apply surface coatings to provide better conductivity, reduced scale growth and Cr
volatility. In this study AISI 430 ferritic stainless steel interconnect was coated in a
cobalt-base pack mixture by pack cementation. The effect of oxide thickness on the
Electrical conductivity was investigated by applying isothermal oxidation. This effect
was also investigated in different temperatures (400-700ºC). The formation of MnCo2O4,
CoCr2O4, CoFe2O4 and Co3O4 spinels during oxidation improved oxidation resistance
and electrical conductivity. Results exhibited that the increase of isothermal oxidation
time and increase of temperature, increased the oxide thickness and this decrease the
electrical conductivity.