New-generation biocompatible Ti-based metallic glass ribbons for flexible implants. (November 2022) - Yüce, Eray
Graphical abstract: Highlights: Five fully biocompatible Ti-based metallic glasses with different metalloid and soft metal content for a synergistic improvement in corrosion properties. For Ti40 Zr40 bearing alloys the GFA drops due to the low negative enthalpy of mixing between Ti and Zr atoms. With increasing Ti and decreasing Zr content, the maximum of the broad diffuse XRD peak shifts to higher 2-Theta angles. Ti60 Zr20 Si8 Ge7 B3 Sn2 and Ti50 Zr30 Si8 Ge7 B3 Sn2 have a very high pitting potential and wider passivation region compared with other Ti-based MG alloys. Abstract: We introduce five new biocompatible Ti-based metallic glass (MG) compositions with different metalloid and soft metal content for a synergistic improvement in corrosion properties. Without any potentially harmful elements such as Cu, Ni or Be, these novel alloys can eliminate the risk of inflammatory reaction when utilized for permanent medical implants. Excluding Cu, Ni or Be, which are essential for Ti-based bulk MG production, on the other hand, confines the glass-forming ability of novel alloys to a moderate level. In this study, toxic-element free MG alloys with significant metalloid (Si–Ge–B, 15–18 at.%) and minor soft element (Sn, 2–5 at.%) additions are produced in ribbon form using conventional single-roller melt spinning technique. Their glass-forming abilities and their structural and thermal properties are comparatively investigated using X-ray diffraction (XRD), synchrotron XRD and differential scanning calorimetry. Their corrosion resistance is ascertained in a biological solution to analyze their biocorrosion properties and compare them with other Ti-based bulk MGs along with energy dispersive X-ray. Ti60 Zr20 Si8 Ge7 B3 Sn2 and Ti50 Zr30 Si8 Ge7 B3 Sn2 MG ribbons present a higher pitting potential and passivation domain compared with other Ti-based MG alloys tested in similar conditions. Human mesenchymal stem cell metabolic activity and cytocompatibility tests confirm their outstanding cytocompatibility, outperforming Ti-Al6-V4.