Abusabir Ahmed, Khan Muhammad A, Asif Muhammad, Khan Kamran A
School of Aerospace, Transport and Manufacturing, Cranfield University, Cranfield MK43 0AL, UK.
Department of Mechanical Engineering, National University of Sciences and Technology, Karachi 75350, Pakistan.
Polymers (Basel). 2022 Feb 5;14(3):618. doi: 10.3390/polym14030618.
Three-dimensional printed polymeric lattice structures have recently gained interests in several engineering applications owing to their excellent properties such as low-density, energy absorption, strength-to-weight ratio, and damping performance. Three-dimensional (3D) lattice structure properties are governed by the topology of the microstructure and the base material that can be tailored to meet the application requirement. In this study, the effect of architected structural member geometry and base material on the viscoelastic response of 3D printed lattice structure has been investigated. The simple cubic lattice structures based on plate-, truss-, and shell-type structural members were used to describe the topology of the cellular solid. The proposed lattice structures were fabricated with two materials, i.e., PLA and ABS using the material extrusion (MEX) process. The quasi-static compression response of lattice structures was investigated, and mechanical properties were obtained. Then, the creep, relaxation and cyclic viscoelastic response of the lattice structure were characterized. Both material and topologies were observed to affect the mechanical properties and time-dependent behavior of lattice structure. Plate-based lattices were found to possess highest stiffness, while the highest viscoelastic behavior belongs to shell-based lattices. Among the studied lattice structures, we found that the plate-lattice is the best candidate to use as a creep-resistant LS and shell-based lattice is ideal for damping applications under quasi-static loading conditions. The proposed analysis approach is a step forward toward understanding the viscoelastic tolerance design of lattice structures.
三维打印聚合物晶格结构因其低密度、能量吸收、强度重量比和阻尼性能等优异特性，最近在多个工程应用领域受到关注。三维（3D）晶格结构的性能由微观结构的拓扑结构和可定制以满足应用需求的基础材料决定。在本研究中，研究了设计的结构构件几何形状和基础材料对3D打印晶格结构粘弹性响应的影响。基于板型、桁架型和壳型结构构件的简单立方晶格结构用于描述多孔固体的拓扑结构。所提出的晶格结构使用材料挤出（MEX）工艺由两种材料制成，即聚乳酸（PLA）和丙烯腈-丁二烯-苯乙烯共聚物（ABS）。研究了晶格结构的准静态压缩响应，并获得了力学性能。然后，对晶格结构的蠕变、松弛和循环粘弹性响应进行了表征。观察到材料和拓扑结构都会影响晶格结构的力学性能和时间相关行为。发现基于板的晶格具有最高的刚度，而基于壳的晶格具有最高的粘弹性行为。在所研究的晶格结构中，我们发现板晶格是用作抗蠕变晶格结构的最佳候选材料，而基于壳的晶格在准静态加载条件下是阻尼应用的理想选择。所提出的分析方法是朝着理解晶格结构的粘弹性公差设计迈出的一步。
