Simulation of Mechanical Behavior and Construction of Regular PLA Scaffolds

In this study, the mechanical properties of one of the most widely used polymeric biomaterials in the body called Poly Lactic Acid (PLA) in the porous state were evaluated. Firstly, the initial regular porous structures, based on the tetrahedron-catheter model known as Kelvin model, were designed for simulating bone tissue, using 3D design software with FDM technique. Afterwards, pressure test was used to determine the mechanical properties and mode of failure. Finally, experimental results were compared with the simulation software analysis results. The results showed that increasing the porosity reduces the strength and the increasing the cell size in a constant porosity results in increased compressive strength. Also, by decreasing the porosity, the amount of the strain up to fracture increases in a relatively constant stress. The brittle failure at 45° in the samples of high porosity was shown. However, the samples with a lower porosity had a relative ductile behavior and as the pressure rises, the cells accumulate on each other and change the form to the fracture point. Comparing the empirical and the simulation results showed that there is a good agreement between them and the simulation model has a high reliability for the porous model.