J. Mater. Sci. Technol. ›› 2017, Vol. 33 ›› Issue (9): 954-960.DOI: 10.1016/j.jmst.2017.01.014
Special Issue: 2017腐蚀与防护专辑; 2017-2018年Mg合金专题
• Orginal Article • Previous Articles Next Articles
Song Yingwei*(), Shan Dayong, Han En-Hou
Received:
2016-10-24
Revised:
2016-11-28
Accepted:
2016-12-21
Online:
2017-09-20
Published:
2017-10-16
Contact:
Song Yingwei
About author:
1 The authors contributed equally to this work.
Song Yingwei, Shan Dayong, Han En-Hou. Pitting corrosion of a Rare Earth Mg alloy GW93[J]. J. Mater. Sci. Technol., 2017, 33(9): 954-960.
Fig 1. BSE microstructure of cast Mg alloy GW93 (a) low magnification of GW93 with network distribution of second phases and light regions in the grain boundaries; (b) magnified morphology of the cubic-shaped and dendritic-shaped second phases.
Region | Mg | Y | Gd |
---|---|---|---|
A region (cubic-shaped second phase) | 89.01 | 4.50 | 6.49 |
B region (dendritic-shaped second phase) | 86.52 | 4.59 | 8.89 |
C region (Mg matrix) | 96.08 | 1.46 | 2.46 |
Table 1 EDX analysis of the chemical composition of Mg matrix, cubic-shaped and dendritic-shaped second phases in cast Mg alloy GW93 (at.%).
Region | Mg | Y | Gd |
---|---|---|---|
A region (cubic-shaped second phase) | 89.01 | 4.50 | 6.49 |
B region (dendritic-shaped second phase) | 86.52 | 4.59 | 8.89 |
C region (Mg matrix) | 96.08 | 1.46 | 2.46 |
Fig. 3. SKPFM Volta potential measurement of cast Mg alloy GW93 (a) Volta potential map with the dark regions corresponding to negative potential and the light regions corresponding to positive potential; (b) Volta potential profile along the white line in (a) which runs through Mg matrix and dendritic-shaped second phases.
Immersion time | Rs (Ω cm2) | Ydl (μS cm-2 s-n) | ndl | Rct (Ω cm2) | Cf (μF cm-2) | Rf (Ω cm2) | L (H cm2) | RL (Ω cm2) |
---|---|---|---|---|---|---|---|---|
0 h | 52.9 | 21.7 | 0.89 | 513.8 | 4419 | 251.3 | 46300 | 919.9 |
6 h | 11.1 | 7.8 | 0.91 | 736.4 | 3112 | 413 | 13120 | 464.2 |
Table 2 Fitting results of the polarization curves of the cast GW93 and after 6 h immersion in 3.5% NaCl solution.
Immersion time | Rs (Ω cm2) | Ydl (μS cm-2 s-n) | ndl | Rct (Ω cm2) | Cf (μF cm-2) | Rf (Ω cm2) | L (H cm2) | RL (Ω cm2) |
---|---|---|---|---|---|---|---|---|
0 h | 52.9 | 21.7 | 0.89 | 513.8 | 4419 | 251.3 | 46300 | 919.9 |
6 h | 11.1 | 7.8 | 0.91 | 736.4 | 3112 | 413 | 13120 | 464.2 |
Fig. 5. EIS spectra of cast GW93 and after 6 h immersion in 3.5% NaCl: (a) Nyquist plots; (b) Bode plots of frequency vs. |Z|; and (c) Bode plots of frequency vs. phase angle.
Rs (Ω cm2) | Ydl (μS cm-2 s-n) | ndl | Rt (Ω cm2) | Yf (μS cm-2 s-n) | nf | Rf (Ω cm2) | L (H cm2) | RL (Ω cm2) | Chi square | |
---|---|---|---|---|---|---|---|---|---|---|
Cast GW93 | 52.8 | 18.9 | 0.91 | 474.5 | 4221 | 0.57 | 275.7 | 23570 | 1032 | 6.1 × 10-4 |
6 h | 7.24 | 8.9 | 0.91 | 657 | 4195 | 0.55 | 505.3 | 16512 | 567.4 | 9.0 × 10-4 |
Table 3 Fitting results of the EIS spectra of the cast GW93 and after 6 h immersion in 3.5% NaCl solution.
Rs (Ω cm2) | Ydl (μS cm-2 s-n) | ndl | Rt (Ω cm2) | Yf (μS cm-2 s-n) | nf | Rf (Ω cm2) | L (H cm2) | RL (Ω cm2) | Chi square | |
---|---|---|---|---|---|---|---|---|---|---|
Cast GW93 | 52.8 | 18.9 | 0.91 | 474.5 | 4221 | 0.57 | 275.7 | 23570 | 1032 | 6.1 × 10-4 |
6 h | 7.24 | 8.9 | 0.91 | 657 | 4195 | 0.55 | 505.3 | 16512 | 567.4 | 9.0 × 10-4 |
Fig. 7. SEM corrosion morphology of cast Mg alloy GW93immersed in 3.5% NaCl for 30 min after removing corrosion products (a) low magnification; and (b) high magnification.
Fig. 8. SEM corrosion morphology of cast Mg alloy GW93 immersed in 3.5% NaCl for 48 h after removing corrosion products (a) low magnification; and (b) high magnification.
Fig. 9. SEM corrosion morphology of cast Mg alloy GW93 immersed in 3.5% NaCl for 72 h after removing corrosion products (a) low magnification; and (b) high magnification.
Fig. 10. Surface morphology of the oxide films formed on cast Mg alloy GW93 after immersion in 3.5% NaCl for 10 h (a) high magnification; and (b, c) low magnification.
Mg | O | Y | Gd | |
---|---|---|---|---|
Mg matrix | 84.55 | 11.97 | 1.49 | 1.99 |
Second phase | 79.42 | 9.64 | 3.97 | 6.97 |
Table 4 EDX analysis of the oxide film formed on Mg matrix and second phases of cast Mg alloy GW93 after immersion in 3.5% NaCl for 10 h (at.%).
Mg | O | Y | Gd | |
---|---|---|---|---|
Mg matrix | 84.55 | 11.97 | 1.49 | 1.99 |
Second phase | 79.42 | 9.64 | 3.97 | 6.97 |
|
[1] | L.Y. Zhao, H. Yan, R.S. Chen, En-Hou Han. Orientations of nuclei during static recrystallization in a cold-rolled Mg-Zn-Gd alloy [J]. J. Mater. Sci. Technol., 2021, 60(0): 162-167. |
[2] | S.G. Wang, M. Sun, S.Y. Liu, X. Liu, Y.H. Xu, C.B. Gong, K. Long, Z.D. Zhang. Synchronous optimization of strengths, ductility and corrosion resistances of bulk nanocrystalline 304 stainless steel [J]. J. Mater. Sci. Technol., 2020, 37(0): 161-172. |
[3] | Yuqiao Dong, Yassir Lekbach, Zhong Li, Dake Xu, Soumya El Abed, Saad Ibnsouda Koraichi, Fuhui Wang. Microbiologically influenced corrosion of 304L stainless steel caused by an alga associated bacterium Halomonas titanicae [J]. J. Mater. Sci. Technol., 2020, 37(0): 200-206. |
[4] | Zhangweijia Qiu, Zhengkun Li, Huameng Fu, Hongwei Zhang, Zhengwang Zhu, Aimin Wang, Hong Li, Long Zhang, Haifeng Zhang. Corrosion mechanisms of Zr-based bulk metallic glass in NaF and NaCl solutions [J]. J. Mater. Sci. Technol., 2020, 46(0): 33-43. |
[5] | Shun Zhang, Yong Sun, Ruizhi Wu, Xiang Wang, Xiao-Bo Chen, Carlos Fernandez, Qiuming Peng. Coherent interface strengthening of ultrahigh pressure heat-treated Mg-Li-Y alloys [J]. J. Mater. Sci. Technol., 2020, 51(0): 79-83. |
[6] | Enze Zhou, Jianjun Wang, Masoumeh Moradi, Huabing Li, Dake Xu, Yuntian Lou, Jinheng Luo, Lifeng Li, Yulei Wang, Zhenguo Yang, Fuhui Wang, Jessica A. Smith. Methanogenic archaea and sulfate reducing bacteria induce severe corrosion of steel pipelines after hydrostatic testing [J]. J. Mater. Sci. Technol., 2020, 48(0): 72-83. |
[7] | Yanan Pu, Wenwen Dou, Tingyue Gu, Shiya Tang, Xiaomei Han, Shougang Chen. Microbiologically influenced corrosion of Cu by nitrate reducing marine bacterium Pseudomonas aeruginosa [J]. J. Mater. Sci. Technol., 2020, 47(0): 10-19. |
[8] | Lifeng Zhang, Shangyi Ma, Weizhen Wang, Zhiqing Yang, Hengqiang Ye. Atomic structure and enhanced thermostability of a new structure MgYZn4 formed by ordered substitution of Y for Mg in MgZn2 in a Mg-Zn-Y alloy [J]. J. Mater. Sci. Technol., 2019, 35(9): 2058-2063. |
[9] | Shude Ji, Shiyu Niu, Jianguang Liu. Dissimilar Al/Mg alloys friction stir lap welding with Zn foil assisted by ultrasonic [J]. J. Mater. Sci. Technol., 2019, 35(8): 1712-1718. |
[10] | Lingyang Yuan, Liming Peng, Jingyu Han, Baoliang Liu, Yujuan Wu, Juan Chen. Effect of Cu addition on microstructures and tensile properties of high-pressure die-casting Al-5.5Mg-0.7Mn alloy [J]. J. Mater. Sci. Technol., 2019, 35(6): 1017-1026. |
[11] | Huijun Guo, Xun Zeng, Jianfeng Fan, Hua Zhang, Qiang Zhang, Weiguo Li, Hongbiao Dong, Bingshe Xu. Effect of electropulsing treatment on static recrystallization behavior of cold-rolled magnesium alloy ZK60 with different reductions [J]. J. Mater. Sci. Technol., 2019, 35(6): 1113-1120. |
[12] | M. Wang, B.B. He, M.X. Huang. Strong and ductile Mg alloys developed by dislocation engineering [J]. J. Mater. Sci. Technol., 2019, 35(3): 394-395. |
[13] | Dan Liu, Ru Jia, Dake Xu, Hongying Yang, Ying Zhao, M. saleem Khan, Songtao Huang, Jiankang Wen, Ke Yang, Tingyue Gu. Biofilm inhibition and corrosion resistance of 2205-Cu duplex stainless steel against acid producing bacterium Acetobacter aceti [J]. J. Mater. Sci. Technol., 2019, 35(11): 2494-2502. |
[14] | Bo Song, Qingshan Yang, Tao Zhou, Linjiang Chai, Ning Guo, Tingting Liu, Shengfeng Guo, Renlong Xin. Texture control by {10-12} twinning to improve the formability of Mg alloys: A review [J]. J. Mater. Sci. Technol., 2019, 35(10): 2269-2282. |
[15] | Mingquan Zhang, Yan Feng, Jinghuai Zhang, Shujuan Liu, Qiang Yang, Zhuang Liu, Rongguang Li, Jian Meng, Ruizhi Wu. Development of extruded Mg-6Er-3Y-1.5Zn-0.4Mn (wt.%) alloy with high strength at elevated temperature [J]. J. Mater. Sci. Technol., 2019, 35(10): 2365-2374. |
Viewed | ||||||
Full text |
|
|||||
Abstract |
|
|||||