Speaker
Description
Lattice structures have gained increasing popularity due to their remarkable strength-to-weight ratio. With advancements in material extrusion additive manufacturing (MEX), complex designs of lattice structures have become more accessible and widely applicable. However, their slender components face the challenges of elastic buckling at low densities.
A novel lightweight additive manufactured stayed polymer lattices [1] is presented based on a previous published theoretical concept [2]. The buckling and post-buckling behaviour of stayed unit cells (UCs) were investigated experimentally through quasi-static uniaxial compression tests [3]. Simulations are conducted using an analytical model based on the general theory of elastic stability, implemented in a Python-based module “Pyfurc” [4].
Through an iterative process of fabrication (via MEX), testing (compression experiments) and simulation (analytical model), the mechanical behaviour of stayed UCs can be tuned by varying geometric parameters to achieve a higher strength-to-weight ratio. The analytical model enables predictive simulations across a broader range of parameters, reducing time and material costs while minimizing the reliance on direct experimental trials.
A set of parameters has been identified that can further enhance the ultimate load of the UCs, such as specific geometrical imperfections or specialized intersection designs. These findings provide a mechanical evaluation of the UCs' design, focusing on their buckling behaviour under varying geometrical parameters, which contributes to the identification of more effective lightweight stayed UC types.
[1] Ou, Y., Köllner, A., Dönitz, A. G., Richter, T. E., & Völlmecke, C. (2024). Material extrusion additive manufacturing of novel lightweight collinear stayed polymer lattices. International Journal of Mechanics and Materials in Design, 1-17.
[2] Zschernack, C., Wadee, M. A., & Völlmecke, C. (2016). Nonlinear buckling of fibre-reinforced unit cells of lattice materials. Composite Structures, 136, 217-228.
[3] Ou, Y.,& Völlmecke, C. (n.d.). Experimental study on the effect of geometric parameters on the buckling behavior of MEX-additively manufactured PLA collinear stayed unit cells. Progress in Additive Manufacturing. [Manuscript submitted for publication].
[4] pyfurc Documentation — pyfurc 0.2.3 documentation. 2023-01-12.
url: https://pyfurc.readthedocs.io/en/latest/ (visited on 07/26/2023).
