جستجوی مقالات مرتبط با کلیدواژه "area specific resistance (asr)" در نشریات گروه "مواد و متالورژی"

Oxidation resistance and electrical conductivity of stainless steels used as interconnects in solid oxide fuel cells can be improved by using a conductive and protective coating layer. In this study, AISI 304 austenitic stainless steel was coated in a cobalt powder base pack mixture. Isothermal oxidation test was used to investigate the oxidation resistance of coated and non-coated steel. Area specific resistance (ASR) was also measured as a function of oxidation time at 800 °C. Microstructure of coated and oxidized samples was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) device. The results showed that cobalt coated samples showed better oxidation resistance than non-coated samples. The results showed that increasing the temperature would increase the area specific resistance. The cobalt coating layer also converted to CoFe2O4, Co3O4 and CoCr2O4 spinels during the isothermal oxidation process. Cobalt spinels exhibited less ASR (27.4 mΩ cm2) compared to the uncoated sample (60.5 mΩ cm2).

In order to increase the efficiency and working life of mettalic interconnects used in solid oxide fuel cells, protective coatings with high electrical conductivity are used. In this study, AISI 430 ferritic stainless steel was coated in a cobalt-base pack mixture by pack cementation. The effect of oxide thickness on the area specific resistance (ASR) was investigated by applying isothermal oxidation at 800 °C and non-isothermal oxidation at a temperature range of 400 – 900 ºC. Results showed that the formation of MnCo2O4 and CoCr2O4 Spinels during oxidation improved electrical conductivity. The increase of isothermal oxidation time and temperature increases the oxide thickness, and consequently the ASR increased.