New Ti-based Ti–Cu–Zr–Fe–Sn–Si–Ag bulk metallic glass for biomedical applications

• Novel Ti47Cu38Zr7.5Fe2.5Sn2Si1Ag2 (at.%) bulk metallic glass (BMG) with a critical diameter of 7 mm was discovered.
• The present BMG is the largest Ni- and Be-free Ti-based BMG containing low content of noble metal reported to date.
• The glassy alloy possesses high specific strength, low Young’s modulus, and good corrosion resistance and bio-compatibility.
• Combination of high glass-forming ability and good mechano- and bio-compatibility for the Ti-based BMG demonstrates the potential for use in biomedical applications.

A novel Ni-free Ti47Cu38Zr7.5Fe2.5Sn2Si1Ag2 (at.%) bulk metallic glass (BMG) with superior glass-forming ability, good mechanical properties and excellent biocompatibility was discovered. The Ti-based BMG with a diameter of 7 mm can be prepared by copper mold casting and the supercooled liquid region was 52 K. Compressive strength, specific strength, Young’s modulus and microhardness of the Ti-based BMG were about 2.08 GPa, 3.2 × 105 N m/kg, 100 GPa and 588 Hv, respectively. Electrochemical measurements indicated that the Ti-based glassy alloy possesses higher corrosion resistance than Ti–6Al–4V alloy in a simulated body fluid environment. Attachment, spreading out and proliferation of MC3T3-E1 cells on the Ti-based BMG surface demonstrated the excellent biocompatibility. Mechanisms of the formation and properties for the Ti-based glassy alloy are also discussed. The combination of high glass-forming ability, excellent mechanical properties, high corrosion resistance and good biocompatibility demonstrates the potential of the Ni-free Ti-based BMG for use in biomedical applications.