Abstract
The Mg-6%Al-3%Zn and Mg-6%Al-3%Zn-(1%, 1.5%, 2%)In alloys were prepared by melting and casting. Their microstructures were investigated via metallographic and energy-dispersive X-ray spectroscopy (EDS) analysis. Moreover, hydrogen evolution and electrochemical tests were carried out in 3.5 wt% NaCl solution aiming at identifying their corrosion mechanisms and discharge behaviors. The results suggested that indium exerts an improvement on both the corrosion rate and the discharge activity of Mg-Al-Zn alloy via the effects of grain refining, β-Mg17Al12 precipitation, dissolving-reprecipitation, and self-peeling. The Mg-6%Al-3%Zn-1.5%In alloy with the highest corrosion rate at free corrosion potential did not perform desirable discharge activity indicating that the barrier effect caused by the β-Mg17Al12 phase would have been enhanced under the conditions of anodic polarization. The Mg-6%Al-3%Zn-1.0%In alloy with a relative low corrosion rate and a high discharge activity is a promising anode material for both cathodic protection and chemical power source applications.
Highlights
Magnesium and its alloys are promising candidates for use in aerospace, vehicle, and electric products due to their high ratio of strength to weight, low density, and good castability [1,2,3].Considerable investigations have been conducted to clarify the corrosion mechanism and to achieve desirable corrosion resistance by designing and developing alloys of high corrosion resistance, inhibitors, and coatings [4,5,6,7,8,9,10,11,12]
The indium containing alloys are denoted as AZI in this work, which is convenient to compare with the AZ63 alloy in the discussion
Value at a scan electrochemical impedance spectroscopy (EIS) tests at free had corrosion potential were after rate of 0.333 mV/s after a steady state of corrosion potential been established
Summary
Magnesium and its alloys are promising candidates for use in aerospace, vehicle, and electric products due to their high ratio of strength to weight, low density, and good castability [1,2,3]. The desirable electrochemical properties of magnesium, including highly negative standard potential ( ́2.34 V vs Standard Hydrogen Electrode (SHE)), high theoretical specific charge capacity (2.2 Ah/g), high theoretical energy density (3.8 Ah/cm3 ) [13] make it an ideal anode material for cathodic protection and power sources [14,15,16,17]. The corrosion and discharge behavior of AZ63 alloys with different indium concentrations (0%, 1%, 1.5%, and 2%) were investigated to clarify the mechanism of indium on activation of AZ magnesium alloys and to find a proper anodic material with negative discharge potential, short incubation time, low self-discharge, and high current efficiency in different conditions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
