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This study aims to fabricate a porous anode coating for solid oxide fuel cells (SOFC) by the flame spraying. Flame spraying is an easy low-temperature process and offers the advantage of a reduced thermal stress. Due to the low-temperature, the initial selection of the feedstock will affect the deposition of the coating. In this study, two kinds of feedstocks were used. One was the commonly used NiO/8YSZ for anode fabrication. The second was the Ni metal with 8YSZ design for the low temperature flame spray. The special nickel-coated graphite (NiGr) was employed as the pore former. The results show that NiO/8YSZ forms a uniform and flat coating with small-sized pores. The Ni/8YSZ powder forms a rough coating containing large-scale pores. The addition of NiGr into the composite powder increases the porosity and permeability of the anode after graphite burn out and hydrogen reduction. In summary, the use of a Ni/8YSZ/NiGr feedstock yields higher porosity (35–40%), gas permeability (1.37 Darcy), bonding strength (45.6 ± 3.18 MPa) and better anode conductivity.

In this study, a (La0.8Sr0.2)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 Ω·cm2. It has good electrical conductivity for SOFC in long-term use.