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

Ti47Cu38-xZr7.5Fe2.5Sn2Si1Ag2Tax (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-6Al-4V 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 bearing 2 at% Ta exhibits the optimal integration of mechanical properties, including the compressive fracture strength exceeding 2000 MPa, relative low Young's modulus of 98 GPa, plastic strain of 3.4% and high hardness of HV 599. 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.