Surface modification of laser‐ and shot‐peened 6082 aluminium alloy: Laser peening effect to pitting corrosion
International Journal of Structural Integrity
ISSN: 1757-9864
Article publication date: 8 March 2011
Abstract
Purpose
The purpose of this paper is to investigate the effect of shock waves and strain hardening effect of laser and shot peening on precipitation‐hardened aluminium alloy AA 6082‐T651.
Design/methodology/approach
The hardened layer was evaluated by means of surface integrity with optical microscopy, scanning electron microscope (SEM), energy dispersive spectroscopy, analysis of microhardness and residual stress profiles. Corrosion anodic polarization tests in a 3.5 per cent NaCl water solution were carried out to express a pitting potential and the degree of pitting attack, which was verified on SEM and with 3D metrology.
Findings
Research results indicated significant differences between two treatment techniques which had an important influence on the final condition of the surface layer. Potentiodynamic polarization tests inferred that laser peening enabled shift of the pitting potential to more positive values, which ensures higher corrosion resistance.
Originality/value
Results confirmed that the higher corrosion resistance of the laser‐peened specimens against pitting corrosion depends on the modification of the surface, due to ablation during plasma generation. Despite increased surface roughness, laser‐peened specimen exhibits beneficial increase of the pitting/breakdown potential and in reduction of pitting attack degree at the specimen surface.
Keywords
Citation
Trdan, U., Žagar, S., Grum, J. and Luis Ocan˜a, J. (2011), "Surface modification of laser‐ and shot‐peened 6082 aluminium alloy: Laser peening effect to pitting corrosion", International Journal of Structural Integrity, Vol. 2 No. 1, pp. 9-21. https://doi.org/10.1108/17579861111108572
Publisher
:Emerald Group Publishing Limited
Copyright © 2011, Emerald Group Publishing Limited