Creep behavior of Ni-12 wt.% Al anodes for molten carbonate fuel cells

Ni-12 wt.% Al anodes are fabricated for use in molten carbon fuel cells by tape casting and sintering. Sintering is performed in three steps, first at 1200 degreesC for 10 min in argon, then at 700 degreesC for 2.5 h in a partial oxidation atmosphere (P-H2 /P-H2O = 10(-2)), and finally at 950 degreesC for 5 min, 30 min or 1.5 h in hydrogen. Three anodes with different phases or microstructures are produced at different reduction times. One anode contains three phases, namely Ni-Al solid solution, Ni3Al, and Al2O3. The amount of Al2O3 is extremely small at 5 min. A second anode also contains the three phases with the amount of Al2O3 comparable with that of Ni3Al at 30 min. Third anode contains two phases, i.e. Ni-Al solid solution and Al2O3 formed at 1.5 h. The creep strains measured for the three anodes after a 100-h creep test are practically the same with an average value of 0.85%. (C) 2002 Elsevier Science B.V All rights reserved.