Mechanical property and biological behaviour of additive manufactured TiNi functionally graded lattice structure  

作　　者：Chaolin Tan Cheng Deng Sheng Li Alessandro Abena Parastoo Jamshidi Khamis Essa Likang Wu Guohua Xu Moataz M Attallah Jia Liu 

机构地区：[1]School of Metallurgy&Materials,University of Birmingham,Birmingham B152TT,United Kingdom [2]Department of Orthopedic Surgery,Second Affiliated Hospital of Naval Medical University,Shanghai 200003,People's Republic of China [3]School of Engineering,University of Birmingham,Birmingham B152TT,United Kingdom [4]School of Mechanical&Automotive Engineering,South China University of Technology,Guangzhou 510640,People's Republic of China

出　　处：《International Journal of Extreme Manufacturing》2022年第4期207-213,共7页极端制造（英文）

基　　金：financially supported by the National Natural Science Foundation of China(52005189);Guangdong Basic and Applied Basic Research Foundation(2019A1515110542 and 2020A1515110699);Guangzhou Foreign Cooperation Projects(2020B1212060049 and 201704030067);Guangdong Academy of Sciences and the University of Birmingham(Contract 17-0551).

摘　　要：Bio-inspired porous metallic scaffolds have tremendous potential to be used as artificial bone substitutes.In this work,a radially graded lattice structure (RGLS),which mimics the structures of natural human bones,was designed and processed by laser powder bed fusion of martensitic Ti-rich TiNi powder.The asymmetric tension-compression behaviour,where the compressive strength is significantly higher than the tensile strength,is observed in this Ti-rich TiNi material,which echoes the mechanical behaviour of bones.The morphologies,mechanical properties,deformation behaviour,and biological compatibility of RGLS samples were characterised and compared with those in the uniform lattice structure.Both the uniform and RGLS samples achieve a relative density higher than 99%.The graded porosities and pore sizes in the RGLS range from 40%-80% and 330-805 µm,respectively,from the centre to the edge.The chemical etching has significantly removed the harmful partially-melted residual powder particles on the lattice struts.The compressive yield strength of RGLS is 71.5 MPa,much higher than that of the uniform sample (46.5 MPa),despite having a similar relative density of about 46%.The calculated Gibson-Ashby equation and the deformation behaviour simulation by finite element suggest that the dense outer regions with high load-bearing capability could sustain high applied stress,improving the overall strength of RGLS significantly.The cell proliferation study suggests better biological compatibility of the RGLS than the uniform structures.The findings highlight a novel strategy to improve the performance of additively manufactured artificial implants by bio-inspiration.

关 键 词：additive manufacturing BIO-INSPIRED graded lattice mechanical properties biological compatibility 

分 类 号：TB34[一般工业技术—材料科学与工程] R318.08[医药卫生—生物医学工程]