Corrosion protection of AA7449-T7951 friction stir welds by laser surface melting with an Excimer laser

Research output: Contribution to journalArticlepeer-review

Authors

  • C. Padovani
  • S.W. Williams
  • E. Siggs
  • A. Groso
  • M. Stampanoni

Colleges, School and Institutes

External organisations

  • Welding Engineering Research Centre
  • Paul Scherrer Institut

Abstract

The corrosion protection afforded by laser surface melting (LSM) AA7449-T7951 friction stir welds was investigated. LSM produced melting of the constituent particles and formation of a homogeneous 3-5 mu m thick layer. Electrochemical tests showed a reduction in cathodic reactivity after LSM. The breakdown potentials, however, did not change significantly, indicating an anodically reactive surface. In situ and ex situ observation after immersion in 0.1 M NaCl showed that LSM reduced the depth attack in the weld region (particularly the HAZ), affording sacrificial protection to the substrate. Delamination of the treatment can occur during corrosion propagation. (C) 2011 Elsevier Ltd. All rights reserved.

Details

Original languageEnglish
Pages (from-to)3956-3969
Number of pages14
JournalCorrosion Science
Volume53
Issue number12
Publication statusPublished - 1 Dec 2011

Keywords

  • Aluminium, Welding