EFFECT OF STRUCTURE DESIGN ON THE COMPRESSIVE STRENGTH AND ENERGY ABSORPTION OF DIFFERENT RESIN-3D PRINTED IRREGULAR VORONOI STRUCTURES BY SLA TECHNIQUE

Nature-like designs inspired designers to adapt them in real-life applications due to their strength and optimal mechanical properties. In the current study, irregular Voronoi structures were prepared through using of Rhinoceros 7Grasshopper software. Both normal and elongated Voronoi designs (based on the columnar joints that exist naturally) were designed, having three separate models per each, homogeneous, gradient I, and gradient II are based on homogeneity and having a core inside the samples. Stereolithography (SLA) three-dimensional (3D) printing was used to fabricate biopolymer Plant-based materials to be prepared for mechanical testing. Generally, the experimental results showed that the proposed Voronoi designs with elongated structures have better mechanical properties. They are about 21% superior to the normal Voronoi structures in terms of resisting deformation and approximately 30 % in energy absorption. Hence, these designs are promising topologies for future applications. Moreover, the failure mode of the six structures occurred due to the collapse in three stages: the cells’ strut fracture, cell collapse, and eventually, fracture growth. In regard to the designed models, the homogeneous model type showed a higher stiffness and ultimate strength while the gradient I model exhibited a higher Young's modulus. Furthermore, the homogeneous and gradient II models showed a great energy absorption property. Besides, the gradient II model possessed the poorest mechanical properties due to its weak geometry design. Hence, this model is not preferred in lightweight-to-strength applications.