Formation and biocompatibility of Ni-Free Zr₆₀Nb₅Cu₂₀Fe₅Al₁₀bulk metallic glass

A Ni-free bulk metallic glass (BMG) of Zr60Nb5Cu20Fe5Al10with a diameter of 3 mm was successfully prepared by copper mold casting. The structure and thermal stability of the BMG were studied by x-ray diffraction (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). It is found that the BMG is apparently of a single amorphous structure and exhibits a wide supercooled liquid region of 101°C A static-state compression revealed that the BMG possesses a superior fracture strength of 1709 MP and extended plastic strain of 9.5%. The corrosion resistance of the BMG was examined by electrochemical polarization in phosphate buffered solution, which demonstrates that the BMG also exhibits an excellent corrosion resistance. Finally, the potential cytotoxicity of the Ni-free BMG was evaluated through cell culture followed by 3-(4,5-Dimethylthiazol-2-yl-)-2,5-diphenyltetrazolium bromide (MTT) assay and scanning electron microscope (SEM) observation. It is shown that the BMG exhibits a high cell viability and proliferation activity, and NIH/3T3 cells can closely adhere and well extend on the surfaces of the BMG alloy. The results indicate that the Ni-free Zr60Nb5Cu20Fe5Al10BMG developed in the present work is promising for biomedical applications.