Additive manufacturing (AM) enables fine control over the architecture and mechanical properties of porous lattice structures. Typical periodic unit cells used in porous structures are inherently anisotropic, may not be suitable for multi-axial applications and cannot reliably create features or struts with low build angle. This study used laser powder bed fusion (PBF) to create isotropic stochastic porous structures in stainless steel (SS316L) and titanium alloy (Ti6Al4V), with modifications that aimed to overcome PBF manufacturing limitations of build angles. The structures were tested in uniaxial compression (n = 5) in 10 load orientations relative to the structure, including the three orthogonal axes. The testing verified that no hidden peaks in elastic modulus existed in the stochastic structure. Modification to the structure reduced the standard deviation of the 10 elastic modulus values from 249 MPa to 101 MPa when made in SS316L and from 95.9 MPa to 52.5 MPa for Ti6Al4V, indicating the structures were more isotropic. These modified stochastic structures have improved stiffness isotropy and could be used for lightweighting and biomaterial applications, reducing the dependence of performance on build orientation, and allowing more flexibility for component orientation on the build platform.

增材制造（AM）可以对多孔晶格结构的结构和机械性能进行精细控制。在多孔结构中使用的典型周期性晶胞固有地是各向异性的，可能不适合多轴应用，并且不能可靠地创建具有低构造角的特征或支柱。这项研究使用激光粉末床熔合（PBF）在不锈钢（SS316L）和钛合金（Ti6Al4V）中创建各向同性的随机多孔结构，并进行了旨在克服PBF制造角度限制的修改。在相对于结构的10个载荷方向（包括三个正交轴）上，对结构进行了单轴压缩（n = 5）测试。测试证明，在随机结构中不存在弹性模量的隐藏峰。对结构的修改将10个弹性模量值的标准偏差从SS316L中降低了249 MPa至101 MPa，对于Ti6Al4V则从95.9 MPa降低至52.5 MPa，表明结构更加各向同性。这些修改后的随机结构具有改善的刚度各向同性，可用于轻量化和生物材料应用，从而降低了性能对构建方向的依赖性，并为构建平台上的组件方向提供了更大的灵活性。