Maximizing the benefit of aluminizing to AZ31 alloy by surface nanocrystallization for elevated resistance to wear and corrosive wear

Surface modification is an effective approach for improving Mg alloys to corrosion and wear. Among various surface techniques, aluminizing is an economical one, which has been applied to various metallic materials for increased resistances to oxidation, corrosion, wear, and corrosive wear. The effectiveness of aluminizing could be further improved by surface nanocrystallization. In this work, effects of surface nanocrystallization on the resistance of aluminized Mg-3Al alloy to corrosion, wear, and corrosive wear were investigated. The results demonstrate that aluminizing increases the resistance of Mg-3Al alloy to wear and corrosion, resulting from introduced passivation capability and hard β-Mg17Al12 phase. Surface nanocrystallization maximizes the benefits, largely attributed to further strengthened surface layer with stronger passivation capability and a more protective film.