Kumar Richi, Solís Cecilia, Trtik Pavel, Kriele Armin, Limberg Wolfgang, Wieland D C Florian, Moosmann Julian, Serdechnova Maria, Blawert Carsten, Ebel Thomas, Willumeit-Römer Regine, Garamus Vasil M
German Engineering Materials Science Centre (GEMS) at Heinz Maier-Leibnitz Zentrum (MLZ), Helmholtz-Zentrum Hereon Lichtenbergstr. 1 85748 Garching Germany
Paul Scherrer Institute 5232 Villigen Switzerland.
RSC Adv. 2025 Feb 10;15(6):4472-4480. doi: 10.1039/d4ra08586h. eCollection 2025 Feb 6.
Hybrid implants consisting of a permanent Ti-based part combined with a degradable Mg part, are promising solutions to design superior implants by combining the advantages of both materials. In these implants Ti provides high strength while a degradable Mg part is used for temporary structural support, bone growth stimulation or drug delivery purpose. As Mg degrades hydrogen gas is released which can ingress into the Ti part, leading to changes in its properties. The profile of hydrogen distribution is a critical parameter for mechanical stability of Ti, especially in long-term applications. To investigate this in microscopic length scale, Ti6Al4V-Mg0.6Zn0.5Ca hybrid samples prepared using metal injection molding were subjected to saline degradation for a period of 0 to 120 hours. Neutron tomography, synchrotron X-ray tomography and diffraction, SEM and gas fusion technique were used to study the ingress of hydrogen in 3D after the degradation of MgZnCa. A uniform distribution of hydrogen was seen radially while the profile along height matched with macroscopic measurements. Synchrotron XRD confirmed that the room temperature diffusion of hydrogen led to lattice expansion of the BCC -phase in Ti6Al4V, while no hydride phases were present.
由永久性钛基部分与可降解镁部分组成的混合植入物,是通过结合两种材料的优点来设计优质植入物的有前景的解决方案。在这些植入物中,钛提供高强度,而可降解镁部分用于临时结构支撑、骨生长刺激或药物递送目的。随着镁降解,会释放出氢气,氢气可能进入钛部分,导致其性能发生变化。氢分布曲线是钛机械稳定性的关键参数,特别是在长期应用中。为了在微观长度尺度上对此进行研究,使用金属注射成型制备的Ti6Al4V-Mg0.6Zn0.5Ca混合样品在盐水中进行了0至120小时的降解。在MgZnCa降解后,利用中子断层扫描、同步加速器X射线断层扫描和衍射、扫描电子显微镜和气体融合技术研究了氢的三维进入情况。观察到氢在径向呈均匀分布,而沿高度的分布曲线与宏观测量结果相符。同步加速器X射线衍射证实,氢在室温下的扩散导致Ti6Al4V中体心立方相的晶格膨胀,同时不存在氢化物相。