Optimization of Selective Laser Sintering Process Parameters Based on PA12 Powders for Bone Tissue Scaffolds

In selective laser sintering (SLS), process parameters are essential to fabricate outstanding mechanical properties products. In this research, process parameters of porous Polyamide 12 (PA12) scaffold were investigated for the sake of obtaining superior mechanical properties. The area energy density (AED) determined by laser power, scanning speed, and scanning space was employed as the main index to assess process parameters. Six groups with different AED were planed, and then cubic and cylindrical samples were modeled and fabricated with PA12 powders via SLS. Afterward, mechanical properties of the samples were measured and studied to achieve optimum parameters. After a detailed comparison of micrograph, density, dimensional accuracy, and mechanical properties of samples under different AED, laser power of 16 W, scanning speed of 2500 m/s, and scanning space of 0.12 mm were found to be the optimum parameters. Further, a 60% uniform porosity scaffold was fabricated with the optimum parameters to measure mechanical properties for evaluating the optimized results, which were elastic modulus of 87.79 MPa, yield strength of 8.25 MPa, and Poisson's ratio of 0.3. Finite element simulation was also performed, and the results exhibited a good agreement with the experimental behaviors.