Selected corrosion properties of the recently developed amorphous Al-Co-Ce alloy system are reported over a range of cobalt and cerium compositions. Improved resistance to halide-induced pitting was observed in 0.6 M NaCl solution when fully amorphous and aged alloys (100degreesC for up to 1000 h) were compared to polycrystalline aluminum. Corrosion behavior was strongly influenced by the cobalt concentration in solid solution in the amorphous state. Tunable corrosion properties based on pre-selection of Co content is shown to be feasible. These corrosion properties remained after heat treatment at 100degreesC. However, complete recrystallization at 550degreesC removed the benefits of the amorphous state. (C) 2004 The Electrochemical Society.