基于功能原理的Gyroid点阵结构塑性屈服强度

Study on plastic yield strength of Gyroid lattice structures based on functional principleson

点阵结构与密实结构存在的力学性能差异之一表现在塑性屈服响应上,因此,研究其屈服行为可为点阵结构的设计和应用提供重要的理论依据。首先,对Gyroid点阵结构进行简化,并基于变形体功能原理建立其力学模型,得到Gyroid点阵结构塑性屈服强度与体积分数之间的映射关系;然后,基于有限元分析软件Abaqus对Gyroid点阵结构准静态压缩过程开展仿真实验,初步验证理论模型的准确性;最后,通过选择性激光熔化(SLM)制备不同体积分数316L不锈钢Gyroid点阵结构,进行单轴压缩实验,分析其变形机制与力学性能。结果表明:理论推导、有限元仿真结果与实验结果相比,误差在25%以内,且根据3种方法结果拟合得到的Gibson-Ashby模型系数具有较好的一致性,表明本文基于理论推导建立的Gyroid点阵结构塑性屈服强度预测模型的有效性。理论模型的构建方法可以转化到其他复杂类型点阵结构中,为快速核算点阵结构力学性能,并将其应用在工程装备中提供理论依据。

One of the differences in mechanical properties between lattice structures and dense structures lies in the plastic yield response.Therefore,studying their yield behavior can provide important theoretical basis for the design and application of lattice structures.Firstly,The Gyroid lattice structure was simplified and its mechanical model was established based on the principle of deformable body function,obtaining the mapping relationship between the plastic yield strength and volume fraction of the Gyroid lattice structure.Then,based on the finite element analysis software Abaqus,simulation experiments were conducted on the quasi-static compression process of Gyroid lattice structures to preliminarily verify the accuracy of the theoretical model.Finally,different volume fractions of 316L stainless steel Gyroid lattice structures were prepared by selective laser melting(SLM),and uniaxial compression experiments were conducted to analyze their deformation mechanism and mechanical properties.The results show that the error between theoretical derivation,finite element simulation results and experimental results is within 25%,and the coefficients of the Gibson-Ashby model fitted based on the results of the three methods have good consistency,indicating the effectiveness of the Gyroid lattice structure plastic yield strength prediction model established based on theoretical derivation.The construction method of theoretical models can be transformed into other complex types of lattice structures,providing a theoretical basis for quickly calculating the mechanical properties of lattice structures and applying them in engineering equipment.