Corrosion behavior of (Zr51.6Cu48.4)93Al7 bulk metallic glass

Corrosion behavior of (Zr51.6Cu48.4)(93)Al-7 bulk metallic glass in 3M HCl, 3M H2SO4, 3M HNO3, 3M NaOH and 3.5 mass%(0.6M)NaCl solutions was studied by immersion test and electrochemical measurements. The bulk metallic glass was spontaneously passivated in the acids, alkali and brine, although it exhibits distinct spontaneous passivation with high passive current density in the Cl-containing solutions. The immersion test indicated, except for 3 M HCl solution, low corrosion rates of the order of 10-2 mm/year for (Zr51.6Cu48.4)(93)Al-7 bulk metallic glass in the other solutions, The quantitative X-ray energy disperse spectroscopy(EDS) analysis revealed that the high corrosion resistance of the bulk metallic glass was due to the formation of aluminium and zirconium-enriched passive film. Corrosion products were mainly copper chloride and oxides in the Cl-containing solutions. The growth mechanism of the passive film is also discussed.