Spiral-eutectic-reinforced Biodegradable Zn-Mg-Ag Alloy Prepared via Selective Laser Melting  

作　　者：Chengde Gao Chuanzhi Li Shuping Peng Cijun Shuai 

机构地区：[1]State Key Laboratory of High Performance Complex Manufacturing,College of Mechanical and Electrical Engineering,Central South University,Changsha,410083,China [2]The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education,Xiangya Hospital,Central South University,Changsha,410078,China [3]Department of Regenerative Medicine&Cell Biology,Medical University of South Carolina,Charleston,SC 29425,USA [4]Institute of Additive Manufacturing,Jiangxi University of Science and Technology,Nanchang,330013,China

出　　处：《Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers)》2022年第2期25-35,共11页中国机械工程学报（增材制造前沿）（英文）

基　　金：supported by Hunan Provincial Natural Science Foun-dation of China(Grant Nos.2020JJ3047,2019JJ50588);National Nat-ural Science Foundation of China(Grant Nos.51935014,82072084,81871498);Jiangxi Provincial Key R&D Projects of China(Grant No.20201BBE51012);Project of State Key Laboratory of High Performance Complex Manufacturing,National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials Open Fund,SCUT(Grant No.2020004);and Project of Hunan Provincial Innovation Foundation for Postgraduates(Grant No.CX20200187).

摘　　要：Zn is a promising biodegradable metal owing to its moderate degradation rate and acceptable biocompatibility.However,the insufficient mechanical strength and plasticity of pure Zn limits its application in bone implants.In this study,a spiral eutectic structure is constructed in Zn-Mg-Ag alloys prepared via selective laser melting to improve their mechanical properties.Results show that the prepared Zn-Mg-Ag alloys are composed of a primary Zn matrix and a eutectic phase,which is composed of alternating𝛼-Zn and an intermetallic compound,MgZn 2.Moreover,the eutectic phase resembles a spiral and increases with Ag content in the alloys.The eutectic pinning effect hinders dislocation and hence results in dislocation accumulation.Meanwhile,the spiral structure alters the propagation direction and dissipates the propagation energy of cracks layer by layer.Consequently,a compressive strength of up to 309±15 MPa and an improved strain of 27%are exhibited in Zn-3Mg-1Ag alloy.Moreover,the Zn-Mg-Ag alloys show high biocompatibility with MG-63 cells and antibacterial activity against Escherichia coli.These findings indicate the potential of spiral eutectic structures for enhancing both the mechanical strength and plasticity of biodegradable Zn alloys.

关 键 词：Selective laser melting Spiral eutectic Zn–Mg–Ag alloy Mechanical properties BIODEGRADABILITY 

分 类 号：TG1[金属学及工艺—金属学]