| Autor: |
ZENG Di - ping, LIU Zhi - yi, WU Hai - jiang, GUO Wen - min, CHEN Dong - rui |
| Jazyk: |
čínština |
| Rok vydání: |
2022 |
| Předmět: |
|
| Zdroj: |
Cailiao Baohu, Vol 55, Iss 8, Pp 117-124 (2022) |
| Druh dokumentu: |
article |
| ISSN: |
1001-1560 |
| DOI: |
10.16577/j.issn.1001-1560.2022.0224 |
| Popis: |
In order to enhance the corrosion resistance of the cast Al - Cu - Mg - Ag alloy, a micro - arc oxidation (MAO) coating was prepared on the surface of the alloy and then sealed with silicone epoxy resin. The corrosion resistance of the Al - MAO coating system before and after sealing treatment was analyzed by electrochemical test, salt spray test and full immersion test. Results showed that after the corrosion test, the cast Al - Cu - Mg - Ag alloy corroded seriously, a large number of corrosion pits appeared along the grain boundary, and the tensile strength of alloy decreased by about 60 MPa; as for the Al - MAO coating system, the corrosion medium corroded the alloy substrate through the micro pores on the surface of the coating, a large number of white spot - like corrosion products appeared on the surface, and its tensile strength decreased by about 25 MPa. The effects of sealing treatment on the Al - MAO coating were as follows: the corrosion current density reduced from 2.62×10-8A/cm2 to 5.52×10-12A/cm2; the corrosion potential positively shifted from -589 mV to -342 mV; the low - frequency impedance increased from～105 Ω·cm2 to ～109 Ω·cm2; after the salt spray test and the full immersion test, no corrosion occurred; and the tensile strength basically remained the same. After the sealing treatment, the surface defects of the MAO coating were sealed, and a dense ceramic - organic composite coating formed on the alloy surface, which greatly reduced the corrosion rate and significantly improved the corrosion resistance of the alloy system. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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