Crystallization and corrosion resistance of Zr–Ti–Y–Al–Cu–Ni–Co–Fe complex multi-component bulk metallic glasses

A series of Zr–Ti–Y–Al–Cu–Ni–Co–Fe complex multi-component bulk metallic glasses (CMBMGs) were designed using multi-substitution strategy in Zr₅₅Cu₃₅Al₁₀, Zr₆₀Cu₃₀Al₁₀ and Zr₆₀Cu₂₈Al₁₂ BMGs, and their crystallization and corrosion behaviors were systematically investigated. It is found that, CMBMGs have higher complexity in crystallization compared to their ternary counterparts, and well-dispersed nano-crystals with diameters of 5–30 nm could be easily formed in CMBMGs in a wide range of annealing temperature, reflecting sluggish crystallization kinetics. Moreover, these CMBMGs exhibit considerable higher corrosion resistance than their ternary counterparts. Besides, both the glass transition temperature (T_g) and onset crystallization temperature (T_x) decrease compared to their ternary counterparts. In addition, it is interesting that the crystallization behavior and corrosion resistance of these Zr–Ti–Y–Al–Cu–Ni–Co–Fe CMBMGs are mainly influenced by the elements substituted in Zr–Cu–Al alloys, which provides a novel route for compositional optimization of CMBMGs. This work is beneficial to better understand the phase formation and properties of BMGs with complex compositions.