Zr–Ti–Al–Fe–Cu bulk metallic glasses for biomedical device application

A series of Zr_63.5−xTi_xAl₉Fe_4.5Cu₂₃ (x = 0, 1.5, 3.0, 4.5, 6.0; at%) bulk metallic glasses (BMGs) were designed and produced by means of copper mold suction casting. The effect of Ti addition on the glass-forming ability (GFA) and mechanical properties of Zr_63.5−xTi_xAl₉Fe_4.5Cu₂₃ alloys was first investigated. The glass-forming ability and room-temperature plasticity of BMGs increase first and then reduced with Ti content increasing. At x = 3.0, the Zr_60.5Ti₃Al₉Fe_4.5Cu₂₃ BMG showed a critical glass formation diameter of 10 mm and excellent room-temperature compressive plasticity (ɛ_P = 4.7%) by using the samples with dimensions of Φ3 mm × 6 mm. Meanwhile, the BMG also showed better biocompatibility and biocorrosion resistance compared with Ti6Al4V alloy. Under the imitated human body condition, the corrosion current density (I_corr) of BMG was 6.61 × 10^–10 A·cm⁻², which is two orders of magnitude lower than that of conventional Ti6Al4V alloy. Moreover, the CCD-986sk cell viabilities are, respectively, 65.4% and 46.6% on the BMG and Ti6Al4V alloy, indicating better biocompatibility of BMG. The Zr_60.5Ti₃Al₉Fe_4.5Cu₂₃ BMG with larger GFA, excellent mechanical properties, biocompatibility and biocorrosion resistance is considered as a potential material in biomedical device fields.