【摘要】 基于选区激光熔化工艺（selective laser melting,SLM）制备的316L不锈钢椭圆截面体心四方点阵结构（elliptic section body-centered tetragonal,E-BCT）是一种抗压性能增强型点阵结构。通过优化传统体心四方（body-centered tetragonal,BCT）点阵结构杆件截面形状，提升点阵结构的压缩性能。基于E-BCT点阵结构数学模型、理论受力模型和铁木辛柯梁理论推导出结构参数与相对密度、等效弹性模量的关系模型。通过选区激光熔化工艺制备不同截面半长轴的E-BCT点阵结构，完成该点阵的静态压缩实验与有限元仿真分析。研究表明，随着椭圆截面半长轴、截面形状系数的增长，E-BCT点阵结构相较于BCT点阵结构性能有较大提升。等效弹性模量最大提升637%，实验与理论、仿真平均误差分别为6.5%、5.1%；屈服强度最大提升654%，实验与仿真平均误差为5.4%；比刚度和比强度分别最大提升308%和321%。更多还原

【Abstract】 The elliptic section body-centered tetragonal(E-BCT) lattice structure of 316L stainless steel fabricated based on selective laser melting(SLM),represents an enhanced lattice structure with improved compressive performance. By optimizing the cross-sectional shape of the struts in the traditional body-centered tetragonal(BCT)lattice,the compressive properties of the lattice structure are significantly improved. Based on the mathematical model of the E-BCT lattice structure,the theoretical force model,and the Timoshenko beam theory, a relationship model is derived between structural parameters and relative density as well as effective elastic modulus. E-BCT lattice structures with varying semi-major axis lengths of the elliptical cross-section are fabricated using the SLM process,and static compression tests and finite element simulations are conducted. The study reveals that as the semimajor axis and shape factor of the elliptical cross-section increase, the performance of the E-BCT lattice structure improves significantly compared to the BCT lattice. The maximum improvement in effective elastic modulus is 637%, with average experimental and theoretical simulation errors of 6.5% and 5.1% respectively. The yield strength shows the maximum increase of654%,with an average experimental and simulation error of 5.4%. Additionally,the specific stiffness and specific strength exhibit maximum improvements of 308% and 321% respectively.更多还原