Work

Corrosion and Volta potential evolution of high purity Mg treated in chloride solutions of bi-valent Cu, Mn, Ni, and Zn cations

Year: 2025

Type: article

Abstract: The corrosion resistance of magnesium-based materials is known to be highly sensitive to even trace amounts of noble impurities. In this study, the surface and electrochemical properties of high-purity magnesium (51 ppm Fe) (HPMg) treated in 1mM chloride solutions of bivalent Cu, Mn, Ni, or Zn cations were investigated by AFM/SKPFM, H2 evolution measurements, DC-polarization, SEM, and XPS. The goal was to understand the potential effects of galvanic replacement induced by the respective cations. The cathodic kinetics drastically increased on HPMg samples treated in Cu solutions. Additionally, the Volta potential difference (VPD) of HPMg increased following treatment in Cu and Zn solutions. Furthermore, the VPD dropped after subsequent exposure to NaCl, which was attributed to the loss of galvanic coupling between magneisum and the noble deposits formed in a galvanic replacement reaction. In contrast, no significant VPD changes were observed on HPMg surface for Mn and Ni treatments. XPS analysis confirmed that Cu and Zn metals/oxides and Mn and Ni hydroxides were displaced by the corrosion film formed on the HPMg after exposure to NaCl. The observed changes in surface properties and corrosion kinetics of HPMg were rationalized.

Source: Corrosion Science

DOI: 10.1016/j.corsci.2025.113360

Authors: K.A. Yasakau, B. Vaghefinazari, N. Scharnagl, S. Lamaka, M.L. Zheludkevich

Institutions: University of Aveiro, Helmholtz-Zentrum Hereon, Christian-Albrechts-Universität zu Kiel

Language: English

Topic: Magnesium Alloys: Properties and Applications

Subfield: Biomaterials

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,070

Funders: Ministério da Ciência, Tecnologia e Ensino Superior, Fundação para a Ciência e a Tecnologia