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Unlabelled: A new a biocompatible Ti42Zr40Ta3Si15 (atomic %) porous bulk glassy alloy was produced by combination of rapid solidification and powder metallurgy techniques. Amorphous alloy ribbons were fabricated by melt spinning, i.e. extremely fast quenching the molten alloy with 10(6)K/s from T=1973K down to room temperature. The ribbons were then cryo-milled at liquid nitrogen temperature in order to produce powder, which was subsequently hot pressed. The resulting thick pellets have a porosity of about 14vol%, a high compression strength of 337MPa and a Young's modulus of about E=52GPa, values very close to those characteristic of cortical bone. Moreover, the morphology of the samples is very similar to that of cortical bone. The biocompatibility, which is due to the absence of any toxic element in the chemical composition, together with the suitable mechanical behavior, make these samples promising for orthopedic and dentistry applications., Statement of Significance: Ti-based alloys are nowadays the standard solution for biomedical implants. However, both the conventional crystalline and amorphous alloys have higher rigidity as the human bone, leading to the damage of the bone at the interface, and contains harmful elements like vanadium, aluminum, nickel or beryllium. The hierarchical porous structures based on glassy alloys with biocompatible elements is a much better alternative. This work presents for the first time the manufacturing of such porous bodies starting from Ti-based amorphous alloy ribbons, which contains only non-harmful elements. The morphology and the compressive mechanical properties of these new products are analyzed in regard with those characteristic to the cortical bone., (Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

This article evaluates the possibility to replace nickel by gallium, which is considered non-toxic for biomedical use, in a Ti-based bulk metallic glass. A new alloy with the atomic composition Ti 41.5 Zr 2.5 Hf 5 Cu 37.5 Ga 7.5 Si 1 Sn 5 free of Ni and other toxic elements was designed and manufactured by means of suction casting the molten alloy into copper molds. Cylindrical rods with diameters up to 3 mm and a length of 50 mm were successfully produced. Further investigations by differential scanning calorimetry and X-ray diffraction in Bragg-Brentano configuration, as well as in transmission using synchrotron radiation, evidenced the main crystalline phases in the new alloy, together with a small content of amorphous matrix. Further in-depth analyses using scanning electron microscopy coupled with elemental mapping, high-resolution transmission electron microscopy and high-angle annular dark-field imaging, revealed a fine microcrystalline structure consisting of γ-CuTi and complex GaTi/CuGaTi intermetallics, together with a remnant amorphous matrix. Such kind of composite samples may open the door for new biomedical devices. [ABSTRACT FROM AUTHOR]