Corrosion wear behaviors of micro-arc oxidation coating of Al2O3 on 2024Al in different aqueous environments at fretting contact

• Published in: Tribology international Vol. 43; no. 5-6; pp. 868 - 875
• Main Authors: DING, Hong-Yan, DAI, Zhen-Dong, SLCUIRY, Suresh C, HUI, David
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Kidlington Elsevier 01.05.2010
• Subjects: Aluminum base alloys; Applied sciences; Bearing steels; Coating; Contact of materials. Friction. Wear; Corrosion; Corrosive wear; Distilled water; Exact sciences and technology; Fretting; Friction; Friction, wear, lubrication; Machine components; Martensitic stainless steels; Mechanical engineering. Machine design; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Sea water; Wear; Artificial rainwater; Corrosive wear; Corrosion wear; Ceramic coating; Fretting wear; Surface metrology; Artificial seawater; Aqueous medium; Friction coefficient; Corrosion test; Ball bearing steel; Oxidation; Profilometer; Microdisplacement; Ball on disk testing; Seawater; Scanning electron microscopy; Distilled water; Aluminium alloy; Corrosion; Stainless steel; Morphology; Groove; micro-arc oxidation; Alumina; Profilometry; Arc surfacing; Room temperature; Tribology
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2009.12.022

The fretting wear behaviour of micro-arc oxidation (MAO) coatings of Al2O3 on an aluminium alloy 2024Al flat against a 440C stainless steel ball was investigated in artificial rainwater, artificial seawater and distilled water by using a ball-on-flat configuration with 300 micron amplitude at room temperature for 1 h. The morphology of the wear scars were analysed using SEM; the 3D-morphology and wear volume-loss were determined using non-contact optical profilometry. Potentiodynamic anodic polarisation was used to measure the corrosion behaviour of the MAO coating before and after the wear test. The influences of the load, frequency and aqueous medium on the friction coefficient and wear volume-loss of the coatings were also analysed. The friction coefficient generally decreased with increasing frequency in the three aqueous solutions, whereas there were varied trends as the load increased. The aqueous environment did significantly influence the friction coefficient, the friction coefficient being the largest when fretting occurred in distilled water, smaller in rainwater, and smallest in seawater. The remarkable antifriction effect of the seawater was noted. The wear-loss of the MAO coating in the distilled water was the largest at low frequency, but it increased rapidly in rainwater and seawater at high frequency due to the corrosion effect of the Cl- ion as well as its accelerating effect on the wear process, resulting in larger wear-loss than that in distilled water, which implies a positive synergism between corrosion and wear.