Insight the long-term biodegradable Mg-RE-Sr alloy for orthopaedics implant via friction stir processing  

作　　者：Yixing Zhu Mengran Zhou Weikang Zhao Yingxin Geng Yujie Chen Han Tian Yifan Zhou Gaoqiang Chen Ruizhi Wu Yufeng Zheng Qingyu Shi 

机构地区：[1]State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment,Department of Mechanical Engineering,Tsinghua University,Beijing,100084,PR China [2]Key Laboratory for Advanced Materials Processing Technology,Ministry of Education,Beijing,100084,PR China [3]Department of Orthopedics,The First Affiliated Hospital of Chongqing Medical University,Chongqing,400016,PR China [4]Key Laboratory of Superlight Materials&Surface Technology(Ministry of Education),Harbin Engineering University,Harbin,150001,PR China [5]School of Materials Science and Engineering,Peking University,Beijing,100871,PR China

出　　处：《Bioactive Materials》2024年第11期293-311,共19页生物活性材料（英文）

基　　金：National Natural Science Foundation of China(Grant No.52305385,Grant No.U23A20541 and Grant No.82102571);China Postdoctoral Science Foundation(2022M710564)and Chongqing Natural Science Foundation(CSTB2022NSCQ-MSX0089).

摘　　要：Magnesium alloys,noted for their substantial mechanical strength and exceptional biocompatibility,are increasingly being considered for use in biodegradable implants.However,their rapid degradation and significant hydrogen release have limited their applications in orthopaedics.In this study,a novel Mg-RE-Sr alloy was created by friction stir processing to modify its microstructure and enhance its degradation performance.Through microstructural characterization,the friction stir processing effectively refined the grains,accelerated the re-dissolution of precipitates,and ensured a uniform distribution of these phases.The processed alloy demonstrated improved comprehensive properties,with an in vitro corrosion rate of approximately 0.4 mm/y and increases in ultimate tensile strength and elongation by 37%and 166%,respectively.Notably,in vivo experiments involving a rat subcutaneous implantation model revealed a slower degradation rate of 0.09 mm/y and a uniform degradation process,basically achieving the requirements for ideal performance in orthopaedic applications.The superior degradation characteristics were attributed to the synergistic effect of attenuated galvanic corrosion and the formation of a dense Y(OH)3/Y2O3 film induced by an exceptional microstructure with a highly solid-soluted matrix and uniformly refined precipitates.Meanwhile,the alloys exhibited excellent biocompatibility and did not cause undesirable inflammation or produce toxic degradation products.These improvements in biocompatibility and degradation characteristics indicate great promise for the use of this friction stir processed alloy in osteosynthesis systems in the clinical setting.

关 键 词：Magnesium ALLOY Friction STIR processing MICROSTRUCTURAL evolution BIODEGRADABLE Biocompatibility 

分 类 号：TG146[一般工业技术—材料科学与工程]