摘要
Gradient ultrafine-grained (UFG) Mg-2Gd-0.4Zr (wt%) alloy sheet, with a UFG layer of about 118 nm on the topmost treated surface, was fabricated by sliding friction treatment (SFT). The corrosion resistance of the SFT-processed UFG surface layer was greatly improved compared to the original coarse-grained (CG) structure, representing as a higher impedance and a lower corrosion rate (CG: 4.11 mm y^(−1), UFG: 2.71 mm y^(−1)). The UFG layer with high density of grain boundaries exhibits an excellent impeditive effect on the cracking of corrosion product films. Compared to the CG sample, the stable corrosion product film inhibits the formation of pitting so providing a better protective effect. In addition, the Gd-rich clusters are randomly distributed after SFT processing, which decreases the tendency of galvanic corrosion on the UFG surface.
基金
financially supported by the National Natural Science Foundation of China(52225101 and 52171103)
the National Key R&D Program of China(2021YFB3701100)
the Project supported by the Graduate Scientific Research and Innovation Foundation of Chongqing,China(CYS18005)
the Fundamental Research Funds for the Central Universities(2020CDJDPT001)
the Natural Science Basic Research Plan in Shaanxi Province of China(Program No.2022JM-233)
Chunquan Liu is grateful for financial support from the Chinese Scholarship Council(CSC No.202106050087).
