Investigation on the Compressive Characteristics and Optimization of Design Parameters of a Novel Functionally Graded Cell Structure

Novel structural conceptualizations frequently incorporate inventive ideas, materials, or construction techniques. This study presents a unique design inspired by the traditional practice of sikku rangoli, a cultural tradition prevalent in the southern region of India, particularly in Tamil Nadu. Because it was novel, it was necessary to optimize the fundamental design for maximal outputs. In contrast to honeycomb structures, intercellular interactions are believed to contribute to the overall strengthening of the structure. By eliminating sharp corners from the structure, stress accumulation is prevented, resulting in improved stress distribution. Therefore, the design aspects that were deemed significant were taken into consideration and through the implementation of experimental design, an optimum design was determined. Utilizing the optimal base design as a foundation, the structure underwent several printing processes using diverse materials and incorporated multiple fillers. Furthermore, the structure was subjected to modifications employing the functional grading design concept. The study employed the functional grading design concept to examine the variations in load bearing capability, load distribution, and failure mode. The findings indicate that the compression strength of the composite structure was mostly influenced by the wall thickness. The combination of a carbon fiber reinforced base material with silicone rubber as filler, together with a functional graded cell structure featuring top and bottom densification, exhibited the highest compression strength compared to all other combinations. In order to investigate the accurate impact of the FG structures, every cell design was printed using PLA-CF, subjected to testing devoid of any additives, and the output parameters were computed. The results indicated that the center densified cell design exhibited significant values for specific energy absorption, relative density, and compressive strength (52.63 MPa, 0.652, and 2.95 kJ kg⁻¹, respectively). The design of the base cell exhibited the greatest crushing force efficacy of 0.982.