电子束选区熔化钛合金点阵材料力学性能研究

目的 研究成型工艺和结构设计对电子束选区熔化技术（SEBM）制备的菱形十二面体Ti6Al4V点阵材料相对密度、形貌和压缩性能的影响。方法 点阵的密度通过测定其尺寸和质量得出，采用电子万能试验机测试点阵结构的压缩性能，采用扫描电子显微镜观察点阵表面形貌。结果 SEBM成形Ti6Al4V支架的相对密度随着熔化功率增加和单胞尺寸减小而增大；以等离子旋转电极雾化技术制备的TC4粉末为原料成型的点阵结构具有优异的塑性，压缩应力—应变曲线平台区域波动小；TC4钛合金菱形十二面体多孔材料的密度与屈服强度和弹性模量的关系满足Gibson-Ashby方程，但指数分别为2.34和2.32。结论 通过调控点阵结构设计和SEBM成型工艺，可控制钛合金的孔隙率和压缩性能，满足骨科植入多孔材料需求。

Study on mechanical properties of lattice structure of titanium alloy manufactured by SEBM

Objective To study the effects of forming process and structure design on the relative density, morphology, and compressibility properties of rhombic dodecahedral Ti6Al4V lattice materials prepared by selective electron beam melting (SEBM).Methods The density of the lattice was obtained by measuring its size and mass. The compressive properties of the lattice structure were tested by an electronic universal testing machine, and the surface morphology of the lattice was observed by a scanning electron microscope.Results The relative density of the TC4 lattice structure formed by SEBM increases with the increase of the melting power and the decrease of the unit cell size. The lattice structure formed by the TC4 powder prepared by the plasma rotating electrode atomization technology as the raw material has excellent plasticity, and the plateau region of the compressive stress-strain curve has small fluctuations. The relationship between the density, yield strength and elastic modulus of the TC4 titanium alloy rhombic dodecahedron porous material satisfies the Gibson-Ashby equation, but the exponents are 2.34 and 2.32, respectively.Conclusion By regulating the lattice structure design and SEBM forming process, the porosity and compression properties of titanium alloys can be controlled to meet the needs of orthopedic implanted porous materials.