Plasma-Sprayed LSM Protective Coating on Metallic Interconnect of SOFC.

In this study, a (La_0.8Sr_0.2)_0.98MnO₃ protective layer was prepared on the C276, Crofer22 APU, SUS304, and SUS430 alloys by the atmospheric plasma spraying technique (APS). The oxidation behavior and electrical property of these metal alloys have been investigated isothermally at 800 °C in air for up to 300 h. Results showed that the ferritic steels transform into MnCr₂O₄ spinels and a Cr₂O₃ layer during isothermal oxidation. The C276 alloy formed NiCr₂O₄ and FeCr₂O₄ layers; these are protective and act as an effective barrier against chromium migration into the outer oxide layer, and the alloy demonstrated good oxidation resistance and a reasonable match to the coefficient of thermal expansion of the substrate and a low-oxide scale area-specific resistance. The ASR effects on the formation of oxide scale have been investigated, and the ASR of coated samples was below 0.024 WΩcm2. It has good electrical conductivity for SOFC in long-term use. [ABSTRACT FROM AUTHOR]