Design and investigation of compressive strength of 3D printed bio-inspired almond-shaped porous structures

In this research, a unit cell was designed for the production of porous materials, taking the almond fruit as a reference. Porous materials are designed in a total of 6 types with the same unit cell size and different wall thicknesses (1, 1.4, and 1.8 mm) as constant and variable porous. A strut was added to the unit cell geometry of these designed structure types in the loading direction, increasing the number of structures to 12. A total of 36 samples were produced, 3 from each structure. Compression tests were applied to the produced samples in a 100 kN capacity compression test device at a loading rate of 2 mm/min. In the tests carried out, the effect of variable wall thickness and vertical struts on the compressive strength of the material and deformation behavior during the compression test was investigated. The unit geometry, designed with reference to the curved and unique structure of the almond fruit, has been decisive on the compression properties and deformation behavior of the material. It has been observed that in samples with variable pore structure, unlike samples with constant pores, deformation occurs at the junctions of the cells and progresses gradually. With a strut added to the unit cell geometry in the loading direction, the compressive strength increased in all samples.