Corrosion interpretation of the novel rare-element bearing bulk metallic glass: Electrochemical, thermodynamic, and surface analysis of the (Cu50Zr43Al7)100-xErx

Bulk metallic glasses (BMGs) have evoked considerable attention in recent years owing to unique properties. However, the surface and anticorrosive properties of this kind of material has not been widely investigated. In this paper, a novel BMG comprises Erbium (Er)-based rare element and high anticorrosive capacity has been introduced. Valorization of Er element (2, 4, 6% at.) in the Cu50Zr43Al7 protective film has been explored from the anticorrosive viewpoint. XRD (X-ray diffraction), GIXRD (Grazing Incidence X-ray Diffraction), AFM (Atomic force microscopy), SEM/EDS (scanning electron microscope/energy-dispersive X-ray spectroscopy), and XPS (X-ray photoelectron spectroscopy) analyses in cooperation with the detailed electrochemical experiments i.e., EIS (Electrochemical Impedance Spectroscopy) and potentiodynamic polarization tests were utilized for surface and corrosion studies. The EIS outcomes have demonstrated that the presence of the Er (at 2% at.) leads to higher corrosion resistance (Rct = 17490 omega cm2, Rtotal = 7590 omega cm2) at different time intervals than the other spec-imens. The proposed mechanism based on surface studies (GIXRD, SEM/EDS, AFM, and XPS) and thermody-namic interpretation imply that the formation of the Er2O3 as a robust protective film along with other types of metal-oxides on the BMG surface is responsible for the high corrosion resistance of this sample.

Automated summary

This paper introduces a novel bulk metallic glass (BMG) containing erbium (Er) element and high anticorrosive capacity. The utilization of Er element (2% at.) in the Cu50Zr43Al7 protective film for its anticorrosive properties was investigated. Surface and corrosion studies were carried out using XRD, GIXRD, AFM, SEM/EDS, XPS, EIS, and potentiodynamic polarization tests. The results showed that the presence of 2% Er element led to higher corrosion resistance at different time intervals compared to other specimens.