Effects of Sm on microstructure and corrosion resistance of hot-extruded AZ61 magnesium alloys


In this study, the effects of Sm on the microstructure and corrosion resistance of hot-extruded AZ61 magnesium alloys were investigated by optical microscopy, scanning electron microscopy, and transmission electron microscopy. The results showed that uniformly dispersed Al2Sm particles with size of ∼2 µm were discovered in the hot-extruded AZ61 magnesium alloy sample modified with 1.0 wt% Sm, which promoted dynamic recrystallization grain growth during the hot-extruded process, gradually increasing the grain of the alloy as Sm content increased. The morphology of the corroded surface and the corrosion rate of the hot-extruded AZ61 magnesium alloy both were significantly improved after Sm addition. The alloy sample modified with 2.0 wt% Sm after immersion in 3.5 wt% NaCl solution for 12 h showed minimum corrosion rate value, 3.1 mg/cm2 day, which is only 3.7% of the corrosion rate of unmodified alloy (82 mg/cm2 day).

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The authors would like to acknowledge the financial support by the National Natural Science Foundation of China (51405216, 51165032), the Natural Science Foundation of Jiangxi Province (20151BAB216018), Ministry of Education Tied up with the Special Research Fund for the Doctoral Program for Higher School (20133601110001), Training Program Foundation for Young Scientist of Jiangxi (20153BCB23023).

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Correspondence to Zhi Hu.

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Hu, Z., Li, X., Hua, Q. et al. Effects of Sm on microstructure and corrosion resistance of hot-extruded AZ61 magnesium alloys. Journal of Materials Research 30, 3671–3681 (2015). https://doi.org/10.1557/jmr.2015.345

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