多孔Ti6Al4V植入体电子束制备及其力学性能

Fabrication of Porous Ti6Al4V Implant Using Electron Beam Melting and Mechanical Properties

采用电子束熔化(EBM)成形工艺,制备蜂窝状多孔Ti6Al4V植入体,分析测试其微观孔隙结构特征、孔隙率和力学性能.通过扫描电镜观测,发现所制备的多孔钛合金植入体具有三维连通孔隙结构,与设计结构相符合,但整体发生了收缩,收缩率约15%.测得多孔植入体的孔隙率为61.5%,相应的抗压强度为172 MPa,弹性模量为3.1 GPa,与人体骨组织弹性模量十分接近.证明EBM技术能够实现对多孔钛合金植入体外形与内部孔隙结构的控制,适用于骨科内植物的制造.

Electron beam melting （EBM） process was used to fabricate porous Ti6Al4V implants with honeycomb structure. The structural and mechanical properties of the fabricated samples were investigated using scanning electronic microscope （SEM） and compression test. The Ti6A14V implants show a three-dimensionally interconnected network. Samples with porosity of （61. 5±3. 2）% have the compressive strength of （172±5） MPa and the elastic modulus of （3.1±0.5） GPa, which are similar to those of human bone. The low stiffness can reduce the stress shielding effects. Overall, the results indicate that the fabricated Ti6Al4V implants have the properties to be potentially employed in orthopedic applications. It is demonstrated that the use of EBM can significantly increase the processing flexibility of metallic implants with controlled internal pore architectures.