Lightweight Ti-Zr-Nb-Al-V refractory high-entropy alloys with superior strength-ductility synergy and corrosion resistance

Effects of Zr Addition on the Microstructural Evolution, Mechanical Properties, and Corrosion Behavior of Novel Biomedical Ti–Zr–Mo–Mn Alloys

“…Based on the previous studies, there are several factors affecting the corrosion behavior of an alloy, which can be categorized into two points: the microstructures and composition of the passivation film. Generally, grain size coupled with phase composition is an important factor affecting the corrosion behaviors of alloys. , An empirical rule for describing the relationship between grain size and corrosion resistance has been proposed by Ralston et al , suggesting that the alloy with finer grain size possessed a higher corrosion resistance, which satisfies well with our testing results . This is because the grain boundary is the main O diffusion channel during the formation and growth of the passivation film, acting as the preferred nucleation point. ,, Increasing the content of Zr in the TZMM alloy system also effectively increased the stability of the β phase by inhibiting the precipitation of the α phase, leading to a reduced microgalvanic corrosion risk, where the α/β phase boundaries are the preferential locations for corrosion attack. , XPS analysis together with the ion-sputtering technique revealed that the passivation films formed on the TZMM alloys exhibit a bilayered structure, with an outer Ti + Zr mixed-oxide layer and inner Zr-oxide-rich layer.…”

“…Generally, grain size coupled with phase composition is an important factor affecting the corrosion behaviors of alloys. 32,41 An empirical rule for describing the relationship between grain size and corrosion resistance has been proposed by Ralston et al, suggesting that the alloy with finer grain size possessed a higher corrosion resistance, which satisfies well with our testing results. 42 This is because the grain boundary is the main O diffusion channel during the formation and growth of the passivation film, acting as the preferred nucleation point.…”