Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8012054 | Transactions of Nonferrous Metals Society of China | 2017 | 16 Pages |
Abstract
Plasma electrolytic oxidation of a cast A356 aluminum alloy was carried out in aluminate electrolytes to develop wear and corrosion resistant coatings. Different concentrations of 2, 16 and 24 g/L NaAlO2 solutions and a silicate electrolyte (for comparison) were employed for the investigation. Wear performance and corrosion resistance of the coatings were evaluated by WC (tungsten carbide) ball-on-flat dry sliding tests and electrochemical methods, respectively. The results show that the coating formed for a short duration of 480 s in 24 g/L NaAlO2 solution generated the best protection. The coating sustained 30 N load for sliding time of 1800 s, showing very low wear rate of â¼4.5Ã10â7 mm3/(N·m). A low corrosion current density of â¼8.81Ã10â9 A/cm2 was also recorded. Despite low α-Al2O3 content of the coating, the compact and nearly single layer nature of the coating guaranteed the excellent performances.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Huan-jun XIE, Ying-liang CHENG, Shao-xian LI, Jin-hui CAO, Li CAO,