Jing Shikai, Li Wei, Ma Guanghao, Cao Xiaofei, Zhang Le, Fang Liu, Meng Jiaxu, Shao Yujie, Shen Biwen, Zhang Changdong, Li Huimin, Wan Zhishuai, Xiao Dengbao
School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China.
China Aerospace Science and Industry Corporation, Beijing 100081, China.
Materials (Basel). 2023 Mar 23;16(7):2545. doi: 10.3390/ma16072545.
Metallic additive manufacturing process parameters, such as inclination angle and minimum radius, impose constraints on the printable lattice cell configurations in complex components. As a result, their mechanical properties are usually lower than their design values. Meanwhile, due to unavoidable process constraints (e.g., additional support structure), engineering structures filled with various lattice cells usually fail to be printed or cannot achieve the designed mechanical performances. Optimizing the cell configuration and printing process are effective ways to solve these problems, but this is becoming more and more difficult and costly with the increasing demand for properties. Therefore, it is very important to redesign the existing printable lattice structures to improve their mechanical properties. In this paper, inspired by the macro- and meso-structures of bamboo, a bionic lattice structure was partitioned, and the cell rod had a radius gradient, similar to the macro-scale bamboo joint and meso-scale bamboo tube, respectively. Experimental and simulated results showed that this design can significantly enhance the mechanical properties without adding mass and changing the printable cell configuration. Finally, the compression and shear properties of the Bambusa-lattice structure were analyzed. Compared with the original scheme, the bamboo lattice structure design can improve the strength by 1.51 times (β=1.5). This proposed strategy offers an effective pathway to manipulate the mechanical properties of lattice structures simultaneously, which is useful for practical applications.
金属增材制造工艺参数，如倾斜角度和最小半径，会对复杂部件中可打印的晶格单元构型施加限制。因此，它们的力学性能通常低于其设计值。同时，由于不可避免的工艺限制（例如，额外的支撑结构），填充各种晶格单元的工程结构通常无法打印或无法达到设计的力学性能。优化单元构型和打印工艺是解决这些问题的有效方法，但随着对性能要求的不断提高，这变得越来越困难且成本高昂。因此，重新设计现有的可打印晶格结构以提高其力学性能非常重要。在本文中，受竹子宏观和细观结构的启发，划分了一种仿生晶格结构，其单元杆分别具有类似于宏观竹节和细观竹管的半径梯度。实验和模拟结果表明，这种设计可以在不增加质量和不改变可打印单元构型的情况下显著提高力学性能。最后，分析了竹节晶格结构的压缩和剪切性能。与原始方案相比，竹节晶格结构设计可将强度提高1.51倍（β=1.5）。该策略为同时控制晶格结构的力学性能提供了一条有效途径，对实际应用具有重要意义。
