【摘要】 为研究激光选区熔化（SLM）增材制造技术的制造方向对点阵结构力学性能的影响，基于不同的打印角度，制备了4组不同相对密度的Ti–6Al–4V面心立方（PC）点阵试样，并开展了力学性能数值仿真、试样微观形貌观测及单轴压缩试验。结果表明，不同打印方向引起的制造缺陷会造成点阵结构等效杨氏模量及失效模式的改变，低密度点阵结构呈现出无特定规律的“逐层坍塌”破坏，高密度点阵结构为整体“剪切”破坏；点阵结构支杆缺陷随打印方向与支杆夹角增大而增大，同时引起点阵结构等效杨式模量的各向异性，低密度点阵结构的制造缺陷对打印方向更敏感，在相对密度为0.1138时，不同打印方向的等效杨氏模量最大差异达14.6%；由于增材制造的内部缺陷，导致基于均质化理论的仿真结果相较试验值偏高。更多还原

【Abstract】 Based on different additive manufacturing building directions, four groups of Ti–6A1–4V primitivecubic(PC) lattice samples fabricated by selective laser melting(SLM) with various relative densities were investigated for the effects of the building directions on the mechanical properties of the lattice structures. The mechanical properties were obtained by numerical simulations and uniaxial compression tests, and the microscopic morphology of the samples defects was analyzed. The results show that the manufacturing defects caused by different building directions will change the effective Young’s modulus in different directions and failure mode of the lattice structure. The specimens with low relative densities collapsed layer by layer randomly, and the high-density lattice structures collapsed by the diagonal shear failure.The lattice structure strut defects caused by SLM increased with the increase of the angle between building direction and the struts, and the defects lead a decrease in effective Young’s modulus. The manufacturing defects of the low-density lattice structures were more sensitive to the building direction, and due to the internal defects of additive manufacturing, the simulation results based on the homogenization theory are higher than the experimental values.更多还原