In Situ Synchrotron X‐Ray Diffraction Characterization of Corrosion Products of a Ti‐Based Metallic Glass for Implant Applications. Issue 21 (16th September 2018) - Gostin, Petre Flaviu
Abstract: Ti‐based bulk metallic glasses are under consideration for implants due to their high yield strength and biocompatibility. In this work, in situ synchrotron X‐ray diffraction (XRD) is used to investigate the corrosion products formed from corrosion of Ti40 Zr10 Cu34 Pd14 Sn2 bulk metallic glass in artificial corrosion pits in physiological saline (NaCl). It is found that Pd nanoparticles form in the interior of the pits during electrochemical dissolution. At a low pit growth potential, the change in lattice parameter of the Pd nanoparticles is consistent with the formation of palladium hydride. In addition, a salt layer very close to the dissolving interface is found to contain CuCl, PdCl2, ZrOCl2 ∙8H2 O, Cu, Cu2 O, and several unidentified phases. The formation of Pd nanoparticles (16 ± 10 nm at 0.7 V vs Ag/AgCl) containing small amounts of the other alloying elements is confirmed by transmission electron microscopy. The addition of albumin and/or H2 O2 does not significantly influence the nature of the corrosion products. When considering the biological compatibility of the alloy, the biological reactivity of the corrosion products identified should be explored. Abstract : Recently developed biocompatible Ti‐based bulk metallic glasses are promising candidates for use in small implants. Here, corrosion products generated in artificial pits on a promising Ti‐based bulk metallic glass are investigated in situ with synchrotron X‐ray diffraction. Results indicate that this metallic glass may release palladium or palladium hydride nanoparticles in service‐relevant conditions with possible significant consequences on biocompatibility.