Abstract Replacing solid structures with lattice structure is a way enabled by additive manufacturing (AM) to realize part lightweight design. Conventional design optimization method based on homogeneous periodic lattice structure cannot achieve the optimal structure without taking the stress magnitude and orientation into account. A design optimization method of heterogeneous conformal lattice structure coupling constraints and anisotropy of AM based on principal stress lines (PSL) is proposed. (1) The PSL is calculated based on finite element analysis to visualize the path of load transfer. (2) The load-adapted lattice structure is generated guided by the PSL. (3) In order to further optimize lattice structure, the lattice structure optimization model is established by coupling anisotropy and constraints of AM based on the fused deposition modeling (FDM) experiment. Taking a cantilever beam as a case, the maximum force-to-weight ratio and the stiffness-to-weight ratio of the optimized heterogeneous conformal lattice structure are increased by 11.8% and 41.8% respectively compared with homogeneous conformal lattice structure, which verified the feasibility of the proposed method.

中文翻译：

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耦合各向异性与增材制造约束的晶格结构设计优化

摘要 用晶格结构代替实体结构是增材制造（AM）实现零件轻量化设计的一种方式。传统的基于均匀周期晶格结构的设计优化方法，如果不考虑应力大小和方向，就无法达到最优结构。提出了一种基于主应力线(PSL)的异质共形晶格结构耦合约束与增材制造各向异性的设计优化方法。(1) 基于有限元分析计算 PSL，以可视化载荷传递路径。(2) 负载适应的晶格结构由 PSL 引导生成。(3) 为了进一步优化晶格结构，基于熔融沉积建模（FDM）实验，通过耦合AM的各向异性和约束建立晶格结构优化模型。以悬臂梁为例，优化后的异质共形晶格结构的最大力重比和刚度重量比分别比均质共形晶格结构提高了11.8%和41.8%，验证了所提出方法的可行性。