Review-Corrosion-Resistant Metastable Al Alloys: An Overview of Corrosion Mechanisms

Commercial aluminum alloys exhibit localized corrosion when exposed to environments containing aggressive anions. Alloying of Al with specific elements (M: Cr, Mo, V, Nb, etc) using non-equilibrium processing techniques has been reported to result in significantly improved corrosion resistance due to the formation of a supersaturated solid solution and uniform distribution of M in the matrix. Several theories describing the corrosion behavior of Al-M alloys have been postulated. This paper presents an overview of the most common non-equilibrium alloying techniques implemented for the production of the metastable Al-M alloys and posited corrosion mechanisms for the improved corrosion resistance. (C) 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.