Compressive strength of metamaterial bones fabricated by 3D printing with different porosities in cubic cells

This research focuses on the compressive strength of metamaterial bones, fabricated by 3D printing with different porosities in cubic cells. For this objective, compressive testing was done on standard samples besides bones, both 3D-printed and real ones. To fabricate a metamaterial bone, the cubic cell was chosen in this research. Since the yield strength and the ultimate stress of the vertical solid standard specimen had better performance than the horizontal solid standard one, the vertical metamaterial sample with a cubic cell was designed for four porosity states of 25%, 30%, 50%, and 55%. The obtained results illustrated that 30% of porosity was introduced as the optimal specimen. Therefore, this percentage of porosity was used to fabricate a metamaterial bone. In addition, the rabbit tibia bone in two solid and metamaterial states was prepared by 3D printing and compared with the real rabbit bone. The results showed that the real bones withstood more force compared to the solid and metamaterial 3D-printed bone samples. The weight of the metamaterial bone decreased by 5.97%, compared to the solid bone specimen. Finally, the quality of 3D printing was checked by microscopy. Then, the quality of 3D printing decreased by increasing the thickness of the strut.