Decreased chromia growth during isothermal and cyclic oxidation tests at 700ºC

Abstract

Improving the accomplishment of solid oxide fuel cells (SOFCs) is one of the problems in this field. Resent researches have enabled to decrease the operating temperature of SOFC from 1000 to 650-800ºC. Chromia forming alloys are the best candidates for interconnects. However, low oxidation resistance of these materials required to be solved to improve interconnect performance. The goal of this study was to coat AISI 430 ferritic stainless steel in a manganese-base pack mixture by pack cementation method. Isothermal oxidation and cyclic oxidation were applied to evaluate the oxide layer thickness. Results showed Spinels forming (Mn3O4 and MnFe2O4) during oxidation improved oxidation resistance. The increase of oxidation time and cycle number increased the oxide thickness. Also the coated substrates oxide layer thickness was remarkably lower compared with uncoated ones in all tests.