Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China.
Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China; International Research Organization for Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-Ku, Kumamoto 860-8555, Japan.
Acta Biomater. 2019 Oct 1;97:23-45. doi: 10.1016/j.actbio.2019.07.038. Epub 2019 Jul 23.
To date, more than fifty articles have been published on the feasibility studies of zinc and its alloys as biodegradable metals. These preliminary in vitro and in vivo studies showed acceptable biodegradability and reasonable biocompatibility in bone and blood microenvironments for the experimental Zn-based biodegradable metals and, for some alloy systems, superior mechanical performance over Mg-based biodegradable metals. For instance, the Zn-Li alloys exhibited higher UTS (UTS), and the Zn-Mn alloys exhibited higher elongation (more than 100%). On the one hand, similar to Mg-based biodegradable metals, insufficient strength and ductility, as well as relatively low fatigue strength, may lead to premature failure of medical devices. On the other hand, owing to the low melting point of the element Zn, several new uncertainties with regard to the mechanical properties of biomedical zinc alloys, including low creep resistance, high susceptibility to natural aging, and static recrystallization (SRX), may lead to device failure during storage at room temperature and usage at body temperature. This paper comprehensively reviews studies on these mechanical aspects of industrial Zn and Zn alloys in the last century and biomedical Zn and Zn alloys in this century. The challenges for the future design of biomedical zinc alloys as biodegradable metals to guarantee 100% mechanical compatibility are pointed out, and this will guide the mechanical property design of Zn-based biodegradable metals. STATEMENT OF SIGNIFICANCE: Previous studies on mechanical properties of industrial Zn and Zn alloys in the last century and biomedical Zn and Zn alloys in this century are comprehensively reviewed herein. The challenges for the future design of zinc-based biodegradable materials considering mechanical compatibility are pointed out. Common considerations such as strength, ductility, and fatigue behaviors are covered together with special attention on several new uncertainties including low creep resistance, high susceptibility to natural aging, and static recrystallization (SRX). These new uncertainties, which are not significantly observed in Mg-based and Fe-based materials, are largely due to the low melting point of the element Zn and may lead to device failure during storage at room temperature and clinical usage at body temperature. Future studies are urgently needed on these topics.
迄今为止，已有五十多篇关于锌及其合金作为可生物降解金属的可行性研究的文章发表。这些初步的体外和体内研究表明，实验用锌基可生物降解金属在骨和血液微环境中具有可接受的生物降解性和合理的生物相容性，并且对于某些合金体系，其机械性能优于镁基可生物降解金属。例如，锌-锂合金表现出更高的 UTS（抗拉强度），而锌-锰合金表现出更高的延伸率（超过 100%）。一方面，与镁基可生物降解金属类似，强度和延展性不足以及相对较低的疲劳强度可能导致医疗器械过早失效。另一方面，由于锌元素的熔点较低，生物医学锌合金的机械性能存在一些新的不确定性，包括抗蠕变性低、易自然时效和静态再结晶（SRX），这可能导致在室温储存和体温使用过程中器械失效。本文全面回顾了上个世纪工业锌及锌合金和本世纪生物医学锌及锌合金在这些机械方面的研究。指出了未来设计作为可生物降解金属的生物医学锌合金以保证 100%机械兼容性所面临的挑战，并将指导基于锌的可生物降解金属的机械性能设计。
本文全面回顾了上个世纪工业锌及锌合金和本世纪生物医学锌及锌合金在这些机械方面的研究。指出了未来设计作为可生物降解金属的生物医学锌合金以保证 100%机械兼容性所面临的挑战。涵盖了强度、延展性和疲劳行为等常见考虑因素，并特别关注了包括抗蠕变性低、易自然时效和静态再结晶（SRX）在内的几个新的不确定性。这些在镁基和铁基材料中没有明显观察到的新不确定性主要是由于锌元素的熔点低，并且可能导致在室温储存和临床使用体温时器械失效。迫切需要对这些课题进行未来研究。
