Partitioning of Zn and its effect on the corrosion of Mg–9Li–1Zn alloy
Journal
Journal of Materials Research and Technology
Journal Volume
41
Start Page
1089
End Page
1105
ISSN
22387854
Date Issued
2026-03
Author(s)
Abstract
Galvanic coupling between α-Mg and β-Li accelerates corrosion of dual-phase Mg–Li alloys, and the formation of Li carbonate has been reported to reduce corrosion. However, the influence of minor alloying elements, such as Zn and Al, on corrosion in dual-phase Mg–Li alloys is less well understood. The microstructure and corrosion behavior of commercial cold-rolled Mg–9Li–1Zn (LZ91) sheets were studied. The effect of Zn on corrosion was elucidated for the first time. The LZ91 sheet had a rolling texture composed of elongated, continuous β-Li and dispersed α-Mg phases, with Zn partitioned mainly in β-Li. Submicron MgLi2Zn second phase resided at β-Li grain boundaries and β-Li/α-Mg interfaces, and fewer inside β-Li grains. During immersion in 0.05 M NaCl, corrosion prevailed in β-Li and was negligible in α-Mg. The MgLi2Zn and β-Li micro-galvanic coupling resulted in the breakdown of the protective corrosion products. This study reveals, for the first time, how the presence of Zn in Mg–Li dual-phase alloys affects corrosion, highlighting that alloying elements and second phases are crucial to the corrosion susceptibility of dual-phase Mg–Li alloys.
Subjects
Galvanic coupling
Mg–Li-Based alloy
Rolling texture
Zn partition
Publisher
Elsevier Editora Ltda
Type
journal article