A Study on Metal 3D Printing Internal Pore Control for the Fabrication of Metal Scaffolds

Abstract

In the treatment of diseases using medical bone scaffolds, it is necessary to design a customized bone scaffold according to the type of individual damage to restore normal bone function based on the damage information of each patient. In addition, the bone scaffold should serve to promote the regeneration of damaged bone in the patient. Compared to a rigid scaffold, a patterned scaffold inserted into a living body promotes bone formation more effectively. Therefore, using a metal 3D printer, it is important to incorporate artificial voids by controlling process variables so that the metal scaffold that replaces damaged bone can form a good bond with live tissue cells. In this study, Ti-6Al-4V ELI, which is actively used in the fields of medical implants and medical devices because of its excellent biocompatibility, was used to fabricate a metal hybrid scaffold that also provides external support. As for the process method, specimen production was conducted by controlling process parameters of the selective laser melting (SLM) method, which is one of the metal 3D printing techniques. Specimens fabricated for each scenario were analyzed by measuring flexural strength, and by imaging via optical microscopy (OM) and scanning electron microscopy (SEM). For OM analysis, the porosity was measured for each case and compared with the flexural strength. Thus, it was possible to adjust the strength by varying the internal pores via the process variables of the metal 3D printer. Accordingly, basic research was conducted to fabricate a metal osseous scaffold with strength similar to that of bone.