熔融沉积成型体心立方点阵结构的压缩性能各向异性

Compressive Properties Anisotropy of BCC Lattice Structure Formed by Fused Deposition Modeling

基于体心立方(BCC)点阵结构设计了1×1、1×2和2×2点阵结构,利用熔融沉积成型(FDM)技术分别制备80%、100%填充率的1×1点阵结构及100%填充率的1×2、2×2点阵结构,并分别对点阵结构进行0°、90°方向的压缩试验,研究不同填充率、不同胞元数量下的压缩性能的各向异性。结果表明:点阵结构的断裂形式为沿着成型材料的堆叠面开裂;2×2点阵结构90°压缩时的压缩强度、压缩模量、总吸能最大,分别达到0.34 MPa、7.85 MPa和4.31 J,较0°时分别提高了13.3%、11.2%和10.4%,在5%应变后的吸能特性最优;100%填充率的1×1点阵结构90°压缩时的比吸能最大,达到206.15 J/kg,较0°时提高了30.66%。对BCC点阵结构力学性能的各向异性研究,为FDM工艺成型点阵结构的工程应用提供依据。

The 1×1,1×2 and 2×2 lattice structures were designed based on body-centered cubic(BCC)lattice structure.The 1×1 lattice structures with 80%and 100%filling rate and the 1×2 and 2×2 lattice structures with 100%filling rate were prepared by fused deposition modeling(FDM)technology,and compression tests were carried out in 0°and 90°directions for the lattice structures,respectively.The anisotropy of compressive properties under different filling rates and different number of lattice units were studied.The results show that the lattice structures exhibit a fracture pattern characterized by cracking along the stacking surface of the formed material.The compressive strength,compressive modulus and total energy absorption of the 2×2 lattice structure at 90°compression are the largest,reaching 0.34 MPa,7.85 MPa and 4.31 J,respectively,which are increased by 13.3%,11.2%and 10.4%compared with that at 0°,respectively.The 2×2 lattice structure demonstrates superior energy absorption characteristics under 5%strain.The 1×1 lattice structure with 100%filling rate has the highest specific absorption energy at 90°compression,reaching 206.15 J/kg,which is 30.66%higher than that at 0°.The anisotropy of the mechanical properties of the BCC lattice structure is studied,which provides a basis for the engineering application of the lattice structure formed by FDM process.