In vitro corrosion properties of HTHEed Mg-Zn-Y-Nd alloy microtubes for stent applications:Influence of second phase particles and crystal orientation  

作　　者：Peihua Du Di Mei Tsuyoshi Furushima Shijie Zhu Liguo Wang Yifan Zhou Shaokang Guan 

机构地区：[1]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [2]Henan Key Laboratory of Advanced magnesium Alloys,Zhengzhou 450002,China [3]Key Laboratory of Advanced Materials Processing and Mold Ministry of Education,Zhengzhou 450002,China [4]Department of Mechanical and Biofunctional Systems,Institute of Industrial Science,The University of Tokyo,4-6-1,Komaba,Meguro,Tokyo 153-8505,Japan [5]Magnesium Innovation Centre-MagIC,Institute of Materials Research,Helmholtz-Zentrum Geesthacht,Geesthacht 21502,Germany

出　　处：《Journal of Magnesium and Alloys》2022年第5期1286-1295,共10页镁合金学报（英文）

基　　金：financial support of Key Projects of the Joint Fund of the National Natural Science Foundation of China(Grant No:U1804251);the National Key Research and Development Program of China(2016YFC1102403,2018YFC1106703 and 2017YFB0702504);China Scholarship Council for the award of fellowship and funding(No.201707040058);China Scholarship Council for the award of fellowship and funding(No.201607040051)。

摘　　要：Magnesium(Mg)alloys are promising materials for cardiovascular stent applications due to their good biocompatibility and biodegradability.However,in vitro and in vivo corrosion tests reveal that Mg alloy stents suffer from a rapid corrosion rate and severe localized corrosion,which is limiting their widespread application.To solve the problem of uneven degradation of stents,a HTHE(long-time and high-temperature heat treatment,large-reduction-ratio hot extrusion)process is used to manufacture Mg-Zn-Y-Nd alloy microtubes in this study.The heat treatment is to dissolve alloying elements and reduce the size of SPPs,and the hot extrusion is to acquire fine-grained and strongly textured microtubes.The microstructural characterization shows that coarse second phases in as-cast alloy are refined and uniformly distributed in matrix of microtubes.After hot extrusion,microtubes show strong texture with basal plain oriented parallel to the longitudinal section(LS).The corrosion testing indicates that severe localized corrosion occurs on the cross section(CS)while localized corrosion is alleviated on the LS.Based on the different corrosion properties of the LS and CS,HTHEed microtubes are promising for solving the problems of rapid corrosion rate and severe localized corrosion of Mg alloy stents.

关 键 词：Mg-Zn-Y-Nd alloy MICROTUBES Heat treatment Hot extrusion Corrosion properties Cardiovascular stent 

分 类 号：R318.08[医药卫生—生物医学工程] TG146.22[医药卫生—基础医学]