Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution
The corrosion behavior of Mg-10Gd–xZn (x = 2, 6 wt.%) alloys in 0.5 wt.% NaCl solution was investigated. Microstructures of both the alloys consisted of (Mg,Zn)3Gd phase and lamellar long period stacking ordered (LPSO) phase. The morphology of the second phase at the grain boundary differed in both...
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KeAi Communications Co., Ltd.
2014-09-01
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Series: | Journal of Magnesium and Alloys |
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Online Access: | http://www.sciencedirect.com/science/article/pii/S221395671400053X |
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author | A. Srinivasan C. Blawert Y. Huang C.L. Mendis K.U. Kainer N. Hort |
author_facet | A. Srinivasan C. Blawert Y. Huang C.L. Mendis K.U. Kainer N. Hort |
author_sort | A. Srinivasan |
collection | DOAJ |
description | The corrosion behavior of Mg-10Gd–xZn (x = 2, 6 wt.%) alloys in 0.5 wt.% NaCl solution was investigated. Microstructures of both the alloys consisted of (Mg,Zn)3Gd phase and lamellar long period stacking ordered (LPSO) phase. The morphology of the second phase at the grain boundary differed in both alloys: it was a continuous network structure in Mg–10Gd–6Zn, whereas it was relatively discrete in Mg–10Gd–2Zn. The dendrites were finer in size and highly branched in Mg–10Gd–6Zn. The corrosion results indicated that the increase in Zn content increased the corrosion rate in Mg–10Gd–xZn alloys. Micro-galvanic corrosion occurred near the grain boundary in both alloys initially as the grain boundary phase was stable and acted as a cathode, however, filiform corrosion dominated in the later stage, which was facilitated by the LPSO phase in the matrix. Severe micro-galvanic corrosion occurred in Mg–10Gd–6Zn due to the higher volume of second phase. The stability of the second phase at the grain boundary was altered and dissolved after the long immersion times. Probably the NaCl solution chemically reacted with the grain boundary phase and de-stabilized it during the long immersion times, and was removed by the chromic acid used for the corrosion product removal. |
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issn | 2213-9567 |
language | English |
last_indexed | 2024-04-24T08:50:26Z |
publishDate | 2014-09-01 |
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series | Journal of Magnesium and Alloys |
spelling | doaj.art-e041c9f509c64c3f99f78a44cbda08952024-04-16T12:12:30ZengKeAi Communications Co., Ltd.Journal of Magnesium and Alloys2213-95672014-09-012324525610.1016/j.jma.2014.08.002Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solutionA. Srinivasan0C. Blawert1Y. Huang2C.L. Mendis3K.U. Kainer4N. Hort5Helmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyHelmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyHelmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyHelmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyHelmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyHelmholtz-Zentrum, Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, 21502 Geesthacht, GermanyThe corrosion behavior of Mg-10Gd–xZn (x = 2, 6 wt.%) alloys in 0.5 wt.% NaCl solution was investigated. Microstructures of both the alloys consisted of (Mg,Zn)3Gd phase and lamellar long period stacking ordered (LPSO) phase. The morphology of the second phase at the grain boundary differed in both alloys: it was a continuous network structure in Mg–10Gd–6Zn, whereas it was relatively discrete in Mg–10Gd–2Zn. The dendrites were finer in size and highly branched in Mg–10Gd–6Zn. The corrosion results indicated that the increase in Zn content increased the corrosion rate in Mg–10Gd–xZn alloys. Micro-galvanic corrosion occurred near the grain boundary in both alloys initially as the grain boundary phase was stable and acted as a cathode, however, filiform corrosion dominated in the later stage, which was facilitated by the LPSO phase in the matrix. Severe micro-galvanic corrosion occurred in Mg–10Gd–6Zn due to the higher volume of second phase. The stability of the second phase at the grain boundary was altered and dissolved after the long immersion times. Probably the NaCl solution chemically reacted with the grain boundary phase and de-stabilized it during the long immersion times, and was removed by the chromic acid used for the corrosion product removal.http://www.sciencedirect.com/science/article/pii/S221395671400053XMg–Gd–Zn alloysMicro-galvanic corrosionPolarizationElectrochemical characterization |
spellingShingle | A. Srinivasan C. Blawert Y. Huang C.L. Mendis K.U. Kainer N. Hort Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution Journal of Magnesium and Alloys Mg–Gd–Zn alloys Micro-galvanic corrosion Polarization Electrochemical characterization |
title | Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution |
title_full | Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution |
title_fullStr | Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution |
title_full_unstemmed | Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution |
title_short | Corrosion behavior of Mg–Gd–Zn based alloys in aqueous NaCl solution |
title_sort | corrosion behavior of mg gd zn based alloys in aqueous nacl solution |
topic | Mg–Gd–Zn alloys Micro-galvanic corrosion Polarization Electrochemical characterization |
url | http://www.sciencedirect.com/science/article/pii/S221395671400053X |
work_keys_str_mv | AT asrinivasan corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution AT cblawert corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution AT yhuang corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution AT clmendis corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution AT kukainer corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution AT nhort corrosionbehaviorofmggdznbasedalloysinaqueousnaclsolution |