Influence of configurational entropy on the corrosion resistance of Pd-based metallic glasses

The corrosion resistance behavior of High-Entropy Metallic Glasses (HE-MGs) has received extensive attention and research due to its wide range of engineering applications. However, research on the relationship between high-entropy properties and corrosion properties is limited, leaving uncertainty about how configurational entropy and high-entropy characteristics affect the corrosion resistance of materials. In this paper, the corrosion behavior of three typical Pd-based Metallic Glasses (MGs) with different entropy values in 0.5 M H 2 SO 4 was investigated. The results show that the self-corrosion current density of Pd-based HE-MG is about 0.3% of that of ternary Pd-based MG with a smaller configurational entropy, which is a large improvement in the corrosion resistance. XPS studies show that the content of Pd in Pd-based HE-MG is only 50% of other Pd-based MGs, but it has the highest increment of Pd oxide after corrosion. The oxide films formed in ternary and quaternary Pd-based MGs are unstable while the Pd-based HE-MG forms a highly stable oxide film that is not prone to dissolution. Moreover, the binding energy was used to directly correlate the corrosion resistance of the material with the stability of the material itself and the surface films. These findings provide a new perspective for subsequent research on regulating the corrosion resistance of MGs through configurational entropy control of high-entropy characteristics. • The different corrosion mechanisms of 3 Pd-based MGs in H 2 SO 4 solution were revealed. • The oxide films formed by Pd 40 Ni 40 P 20 MG and Pd 40 Cu 30 Ni 10 P 20 MG are unstable. • Pd 20 Pt 20 Cu 20 Ni 20 P 20 HE-MG forms a single, uniform and stable oxide film. • The binding energy correlates the corrosion resistance with the oxide stability. • Configurational entropy has a positive effect on the anti-corrosion behavior of MGs.