Introduction of 3D-printed porous structures with interconnected porosities via rotation of each layer around a normal axis: Investigating the effects of annealing and printing parameters on the compressive strength and modulus of the structures

Abstract This study introduces 3D-printed porous structures made of polylactic acid (PLA) with interconnected porosities for tissue engineering as an alternative to bone scaffolds. Then the effects of process parameters and annealing heat treatments on the compressive strength and modulus of the porous samples have been investigated. The examined parameters include extrusion width, layer height, infill pattern, and infill percentage. To create porous structures with interconnected porosities, the infill pattern is rotated by eighteen degrees in each layer, forming new porous structures that can be utilized as bone scaffolds in tissue engineering. After evaluating the compressive mechanical properties of the samples and examining the effects of printing parameters on them, similar samples were subjected to heat treatment, and their compressive mechanical properties were also investigated. The results indicate that the maximum compressive strength and modulus occur in the sample with an extrusion width of 0.6 mm, a layer height of 0.25 mm, a wiggle infill pattern, and a maximum infill percentage. The un-heat-treated sample’s compressive strength and modulus values are 84.51 MPa and 2.28 GPa, respectively. In contrast, these values are 105.44 MPa and 2.29 GPa for the heat-treated sample.