The impact of machining on the corrosion behaviour of AA7150-T651 aluminium alloy

Bing Liu, Xiao Rong Zhou

    Research output: Contribution to journalArticlepeer-review

    Abstract

    In the present study, the corrosion behaviour of machined AA7150-T651 aluminium alloy has been investigated. It was revealed that a near-surface deformed layer with thickness of 500 nm, characterized by ultrafine grains, is present between the alloy surface and the bulk alloy. In the deformed layer, the MgZn2 precipitates were absent, while segregation bands developed at the grain boundaries. The presence of the segregation bands, rich in magnesium and zinc, promoted localized corrosion in the deformed layer. Potentiodynamic polarization of the alloy in deaerated 3.5 wt. % sodium chloride solution revealed current surges at potentials of -750 mV (SCE) and -670 mV (SCE) respectively. The second current surge was associated with the fast dissolution of the deformed layer. Immersion testing of the alloy in 3.5 wt. % sodium chloride solution showed that the deformed layer acted as anode while the bulk alloy served as cathode during corrosion process. © (2014) Trans Tech Publications, Switzerland.
    Original languageEnglish
    Pages (from-to)217-222
    Number of pages5
    JournalMaterials Science Forum
    Volume794-796
    DOIs
    Publication statusPublished - 2014

    Keywords

    • AA7150-T651 aluminium alloy
    • Corrosion
    • Deformed layer
    • Machining

    Fingerprint

    Dive into the research topics of 'The impact of machining on the corrosion behaviour of AA7150-T651 aluminium alloy'. Together they form a unique fingerprint.

    Cite this