Elastic properties prediction of two- and three-dimensional multi-material lattices

• Published in: Thin-walled structures 2024-08, Vol.201, p.112015, Article 112015
• Main Authors: Mostofizadeh, Parham, Dorey, Robert A., Mohagheghian, Iman
• Format: Article
• Language: English
• Subjects: Anisotropy; Lattice materials; Multi-material additive manufacturing; Stiffness
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2024.112015

•2D and 3D multi-material lattices were designed and manufactured.•Analytical models were modified to be applicable to the multi-material lattices.•Homogenization-based models were applied to the designed lattices.•A comparison was conducted between the developed models, FEA, and experiment.•Anisotropy of the 3D lattice was studied with different material arrangements. Advances in multi-material additive manufacturing have opened unprecedented new opportunities for the design and manufacture of lightweight multifunctional structures. The ability to create complex topologies, at a relatively fine resolution, in addition to controlling the material composition on a voxel basis have significantly expanded the design space. To explore this large design space efficiently, accurate and cost-effective modeling tools are essential. In this paper, mechanics-based models for predicting the elastic properties of multi-material 2D and 3D lattice structures are developed or extended. The outcomes are compared with the predictions obtained from finite element models and experimental data. The results reveal that the adapted analytical models demonstrate good accuracy in predicting the elastic modulus of multi-material lattices for relative densities up to approximately 25 % while have considerably less computational cost compared to finite element using solid elements (providing the most accurate results in comparison with experiment). Careful consideration of the accuracy of the predictions is necessary for the use of these models for lattices with high relative density values. Besides, several homogenization-based models were studied to investigate their applicability to multi-material lattice structures when the assumption of scale-separation is considered valid. The capability of these models in predicting the whole elasticity tensor and the potential of multi-material lattices in manipulating the anisotropy are demonstrated. Finally, the introduced prediction frameworks are compared in order to provide an overview of their respective advantages and disadvantages in the case of multi-material lattice structures. [Display omitted]