Ti-Zr-Cu-Fe-Sn-Si-Ag-Ta bulk metallic glasses with good corrosion resistance as potential biomaterials

Ti47Cu38-xZr7.5Fe2.5Sn2 Si1 Ag2 Tax（x=1-4;at%,the same below） bulk metallic glasses（BMGs） with good bio-corrosion resistance and mechanical properties were fabricated by copper mold casting.Critical diameter of the Ti-based BMGs with 1 at%-4 at% Ta was 3 mm.The Ta-incorporated Ti-based BMGs exhibit higher open current potential and parallel passive current density in comparison with those of Ti-6 Al-4 V alloy in 0.9 wt%NaCl and Hank's solution,implying their good corrosion resistance.The pitting corrosion potential of the Ti-based BMGs gradually increases up to about 1.25 V with Ta addition increasing up to 4 at% in 0.9 wt% NaCl solution.Among the present Ti-based BMGs,the alloy bearing2 at% Ta exhibits the optimal integration of mechanical properties,including the compressive fracture strength exceeding 2000 MPa,relative low Young's modulus of98 GPa,plastic strain of 3.4% and high hardness of HV599.The Ta-bearing Ti-based bulk metallic glasses with integration of relative high GFA,good mechanical properties and high bio-corrosion resistance are beneficial for biomedical applications.