Cold sprayed Cu-Ni-Fe anode for Al production

Inert anodes for Al electrolysis were produced by cold spray deposition of mechanical alloyed 65Cu20Ni15Fe powder. No structural change of the 65Cu20Ni15Fe alloy was observed during the cold spray processing apart from a small crystallite size increase. The electrochemical characterization was performed at 700 °C in a potassium cryolite-based electrolyte. A progressive increase of the cell voltage was observed during the 50 h of electrolysis. This is thought to reflect a decrease of the electrical conductivity of the anode attributed to the accumulation of electrolyte at the oxide/alloy interface and to the formation of insulating FeF2 precipitates in the bulk alloy.