A study on the corrosion behavior of the in-situ Ti-based bulk metallic glass matrix composites in acid solutions

Corrosion behavior of the in-situ Ti-based bulk metallic glass matrix composites (BMGMCs) with a nominal composition of Ti42.3Zr29.1Cu6.6Nb6Be16 was studied in HCl and H2SO4 solutions with different concentrations. Potentiodynamic polarization tests indicated that at the lower solution concentration the corrosion current densities barely changed and their values were in the 10(-7) - 10(-8) order of magnitude. However, corrosion current densities increased as the acid concentrations increased. Additionally, stable passivation films formed in the chloride-free solutions after polarization, but passive film breakdown and pitting corrosion were observed in HCl solution. Furthermore, the selective dissolution occurred in the amorphous matrix. Protective oxide films were enriched with Ti, Zr, and Nb oxides according to the XPS analysis after polarization on the surface. For a comprehensively study on the corrosion resistance of the BMGMCs, there also compared corrosion behavior of the composites with 316 stainless steel, Ti-6Al-4V and Zr-45Ti-5Al-3V alloys. It presents us a new reference value on the application of amorphous composites in their functioning environments. (C) 2018 Elsevier B.V. All rights reserved.