Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/15149
Title: The effect of excimer laser surface treatment on the pitting corrosion fatigue behaviour of aluminium alloy 7075
Authors: Chan, CP
Yue, TM 
Man, HC 
Issue Date: 2003
Publisher: Springer
Source: Journal of materials science, 2003, v. 38, no. 12, p. 2689-2702 How to cite?
Journal: Journal of materials science 
Abstract: An excimer laser (KrF) operating at a wavelength of 248 nm was used to modify the surface microstructure of 7075-T651 aluminium alloy. The aim was to improve both the corrosion resistance and the pitting corrosion fatigue resistance of the alloy by means of laser surface melting (LSM). The microstructure and the phases of the modified surface structure were analysed, and the corrosion behaviour of the untreated and the laser-treated specimens were evaluated by immersion test The fatigue resistance of the 7075 alloy has been presented in the form of S/N curves. A microscopical examination and the transmission electron microscopy (TEM) study revealed that LSM caused a reduction both in number and size of constituent particles and a refinement of the grain structure within the laser melted zone. As a result, the corrosion resistance of the aluminium alloy was improved. There was a significant reduction in the number of corrosion pits and shallow attack occurred. The fatigue test results showed that under dry fatigue conditions, the total fatigue life of the laser treated specimens, in which the crack initiation period is of considerable significance, was lower than that of the untreated specimens. However, after shot peening, the fatigue life of the laser treated specimens was recovered. This was primarily attributed to the elimination of surface defects, but also be in part, due to the introduction of compressive residual stresses in the surface layer of the specimen. The fatigue resistance of the shot peened laser-treated specimens, tested in 3.5 wt% NaCl solution with 48 hrs prior immersion, was greater than the untreated specimens with an increase of two orders of magnitude in fatigue life. This was primarily due to the elimination of surface defects and the reduction of corrosion pits.
URI: http://hdl.handle.net/10397/15149
ISSN: 0022-2461
EISSN: 1573-4803
DOI: 10.1023/A:1024498922104
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

21
Last Week
0
Last month
0
Citations as of Apr 10, 2018

WEB OF SCIENCETM
Citations

20
Last Week
0
Last month
0
Citations as of Apr 17, 2018

Page view(s)

69
Last Week
0
Last month
Citations as of Apr 15, 2018

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.