Low-cost Zr-based bulk metallic glasses for biomedical devices applications

Abstract

Toxic element-free and low-cost Zr-based bulk metallic glasses (BMGs) with a property combination of high glass forming ability, large room-temperature plasticity and good biocompatibility are vital candidates as biomedical devices materials. In the present work, the critical diameter (dmax), thermal glass stability, room-temperature mechanical properties, cytotoxicity, corrosion and wear resistances of a series of Zr63.5-xHfxAl9Fe4.5Cu23 (x = 0.0, 1.5, 3.0, 4.5, 6.0, at.%) alloys have been investigated. The Zr60.5Hf3Al9Fe4.5Cu23 (x = 3.0) BMG alloy is found to combine a centimeter scale dmax with large room-temperature plasticity (ɛP = 4.0%). The electrochemical and immersion tests showed the BMG exhibits good corrosion resistance in phosphate buffered solution (PBS) open to air at 37 °C. The passive current density is 9.2 × 10−9 A/cm2, which is one order of magnitude lower than Ti6Al4V alloy at same condition. In addition, the cytotoxicity tests reveal higher cell viability with CCD-986sk cells on the BMG substrate than on Ti6Al4V alloy, showing that the BMG had good biocompatibility. Cell morphologies on the BMG and Ti6Al4V substrates exhibit better cell adhesion of the BMG in comparison with that of Ti6Al4V alloy. Furthermore, the dry wear test shows the wear mass loss is <1/4 of Ti6Al4V alloy at same condition. The attainment of the combination of lower cost and excellent properties suggests that the Zr60.5Hf3Al9Fe4.5Cu23 BMG can be a promising biomedical device material.