Binary Zn-Ti alloys for orthopedic applications: Corrosion and degradation behaviors, friction and wear performance, and cytotoxicity

• 作者: Kun Wang Xian Tong Jixing Lin Aiping Wei Yuncang Li Matthew Dargusch Cuie Wen
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（15）
• 页码范围: 216-229
• 页数: 14页
• 语种: 英文

摘要

Zinc (Zn) and its biocompatible and biodegradable alloys have substantial potential for use in orthopedic implants.Nevertheless,pure Zn with a hexagonal close-packed crystal structure has only two independent slip systems,therefore exhibiting extremely low elongation and yield strength in its ascast condition,which restricts its clinical applications.In this study,as-cast Zn-xTi (titanium) (x =0.05,0.10,0.20,and 0.30 wt.％) binary alloys were hot-rolled and their microstructures,mechanical properties,wear resistance,and cytocompatibility were comprehensively investigated for orthopedic implant applications.The microstructures of both as-cast and hot-rolled Zn-xTi alloys consisted o fan α-Zn matrix phase and a TiZn16 phase,while Zn-0.2Ti and Zn-0.3Ti exhibited a finer α-Zn phase due to the grainrefining effect of Ti.The hot-rolled Zn-0.2Ti alloy exhibited the highest yield strength (144.5 MPa),ultimate strength (218.7 MPa),and elongation (54.2％) among all the Zn-xTi alloys.The corrosion resis-tance of Zn-xTi alloys in Hanks' solution decreased with increasing addition of Ti,and the hot-rolled Zn-0.3Ti alloy exhibited the highest corrosion rates of 432 μm/y as measured by electrochemical testing and 57.9 μm/y as measured by immersion testing.The as-cast Zn-xTi alloys showed lower wear losses than their hot-rolled counterparts.The extracts of hot-rolled Zn-xTi alloys at concentrations of ≤ 25％ showed no cytotoxicity to MG-63 osteosarcoma cells and the extracts of Zn-xTi alloys exhibited enhanced cytocompatibility with increasing Ti content.