The effect of oxidation on the corrosion resistance and mechanical properties of a Zr-based metallic glass

The oxidation kinetics of the Zr64Cu16Ni10Al10 bulk metallic glass (BMG) roughly follows a two-stage rate law at both 433 and 593 K in air. An oxide film of 940 nm can be formed by oxidation at 593 K, which is ZrO2-enriched but Cu-depleted on the outer surface. The oxide film leads to a superior passivity in 0.5 M NaCl and great corrosion resistance improvements in other solutions. The oxidation effect on mechanical properties were characterized by nanoindentation, wedge indentation and compression tests. The Zr-based BMG still keeps the amorphous nature and its good mechanical properties are retained after oxidation.

After oxidation at 593 K for 5 h, the Zr-based metallic glass exhibits superior passivation behavior in 0.5 M NaCl solutions. The corrosion behavior of BMG in 0.5 M H2SO4 and 0.5 M H2SO4 + 0.1 M NaCl is also modified by oxidation. The improvement on the passivity and corrosion resistance is due to the ZrO2-enriched oxide film which is formed during thermal oxidation..Figure optionsDownload as PowerPoint slideHighlights
► Oxidation effect on the corrosion behavior of Zr-based metallic glass was studied.
► The oxidized alloy exhibits superior passivity in 0.5 M NaCl solutions.
► A 110 nm ZrO2-enriched oxide film was formed by oxidation by XPS.
► The BMG’s surface elastic modulus was greatly increased by oxidation.
► The as-prepared and oxidized samples exhibit nearly the same compression plasticity.