Corrosion Resistance of Pd43Cu27Ni10P20 Bulk Metallic Glass

The corrosion behavior Pd43Cu27Ni10P20 bulk metallic glass (Pd-BMG) was investigated in 1.00 M HCl, 1.00 M NaOH and Hanks' solution, a simulated body fluid. The near-surface region has been quantitated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), electrochemical voltammetry and x-ray photoelectron spectroscopy (XPS). The corrosion rates were calculated using an electrochemical method based on the current behavior in the region near open cell potential. Based on average corrosion rate, the Pd-BMG performed slightly poorer than either stainless steel 316 or Ti-6Al-4V in neutral or basic electrolyte solutions, but exceled in acidic media due to the formation of a Pd-dominated inactive surface. Anodic dealloying behavior of Pd-BMG in 1.00 M HCl solution was also investigated. A Pd-dominated porous black film was formed on the sample surface.