Corrosion behavior of nano-treated AA7075 alloy with TiC and TiB2 nanoparticles

High-strength Al alloys like Al-Zn-Mg-Cu series are susceptible to corrosion attacks. Nano-treating is an emerging metallurgical method to enhance their performance. However, there lacks an understanding of nanoparticles’ effects on their corrosion. In this study, corrosion performance of two nano-treated cast and extruded AA7075 alloys (with TiC and TiB 2 ) was investigated. Their dynamical corrosion characteristics on freshly exposed, passivated, and immersed surfaces were compared. The interplays among microstructures, oxidation passivation, and corrosion were revealed. The results show nano-treating enhances corrosion resistance of AA7075, particularly localized corrosion resistance. This study has advanced the multi-scale understanding of corrosion in nano-treated AA7075. • The overall corrosion performance of nano-treated AA7075 alloys (cast and extruded AA7075-TiB 2 /-TiC) were investigated. • The corrosion processes on different representative surface conditions were compared. • The interplay between microstructures, oxidation passivation, and corrosion has been clarified. • Enhanced resistance against corrosion, particularly localized corrosion, has been achieved in nano-treated AA7075 alloys.