中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 30 No. 12 December 2020 |
（1. College of Energy Engineering, Yulin University, Yulin 719000, China;
2. Yulin Key Laboratory of Metal Matrix Composites and Remanufacturing Technology, Yulin University, Yulin 719000, China）
Abstract:The influence of multipass high rotating speed friction stir processing (FSP) on the microstructure evolution, corrosion behavior, and tensile properties of the stirred zone (SZ) was investigated by EBSD, TEM, SEM, electrochemical workstation and electronic universal testing machine. The mean grain size of the SZ is significantly refined, and it increases with the increase of the processing pass. In addition to an obvious increase in the number, the distribution of β-Al12Mg17 precipitates also becomes more uniform and dispersed with increasing the processing pass. Compared with the as-received AZ31 alloy, the tensile properties of the SZ are hardly improved, but the corrosion resistances are significantly enhanced. The corrosion potential of the SZ prepared by 4-pass FSP is increased from -1.56 V for the unprocessed AZ31 alloy to -1.19 V, while the corrosion current is decreased from 1.55×10-4 to 5.47×10-5 A.
Key words: AZ31 alloy; high rotating speed; multipass friction stir processing; microstructure evolution; corrosion resistance; mechanical properties
