Biodegradation of Mg-14Li alloy in simulated body fluid: A proof-of-concept study

作     者：Xiao-Bo Chen Chuanqiang Li Daokui Xu 

作者机构：School of EngineeringCollege of ScienceEngineering and HealthRMIT UniversityCarltonVIC 3053Australia Department of Materials Science and EngineeringMonash UniversityClayton3800VICAustralia Key Laboratory of Nuclear Materials and Safety AssessmentInstitute of Metal ResearchChinese Academy of SciencesShenyang110016China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang110819China 

出 版 物：《Bioactive Materials》 (生物活性材料（英文）)

年 卷 期：2018年第3卷第1期

页      面：110-117页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：the financial support from the Australian Research Council(ARC)through Linkage scheme(LP150100343) C.L.is supported by China Scholarship Council(CSC) 

主　　题：Biodegradable materials Magnesium-lithium alloys MEM SEM Potentiodynamic polarisation 

摘      要：High corrosion kinetics and localised corrosion progress are the primary concerns arising from the clinical implementation of magnesium(Mg)based implantable *** this study,a binary Mglithium(Li)alloy consisting a record high Li content of 14%(in weight)was employed as model material aiming to yield homogenous and slow corrosion behaviour in a simulated body fluid,*** essential medium(MEM),in comparison to that of generic Mg alloy AZ31 and biocompatible Mg-0.5Zn-0.5Ca *** electron microscopy examination reveals single-phase microstructural characteristics of Mg-14Li(b-Li),whilst the presence of insoluble phases,cathodic to a-Mg matrix,in AZ31 and *** slight differences exist in the corrosion kinetics of all the specimens over a short-term time scale(no longer than 60 min),as indicated by potentiodynamic polarisation and electrochemical impedance spectroscopy,profound variations are apparent in terms of immersion tests,*** loss and hydrogen evolution measurements(up to 7 days).Cross-sectional micrographs unveil severe pitting corrosion in AZ31 and Mg-0.5Zn-0.5Ca,but not the case for Mg-14Li.X-ray diffraction patterns and X-ray photoelectron spectroscopy confirm that a compact film(25 mm in thickness)consisting of lithium carbonate(Li2CO3)and calcium hydroxide was generated on the surface of Mg-14Li in MEM,which contributes greatly to its low corrosion *** is proposed therefore that the single-phase structure and formation of protective and defect-free Li2CO3 film give rise to the controlled and homogenous corrosion behaviour of Mg-14Li in MEM,providing new insights for the exploration of biodegradable Mg materials.