Systematic evaluation of selective fusion additive manufacturing based on thermal energy source applied in processing of titanium alloy specimens for medical applications

In this study, two selective metal fusion additive manufacturing (AM) technologies, electron-beam melting (EBM) and selective laser melting (SLM), were used to fabricate Ti6Al4V test specimens for a comprehensive evaluation, including physical-chemical properties and biological properties. The results indicated that the mechanical behaviors, for instance tensile strength and yield strength, of the processed metal devices could exhibit different outcomes with the use of fusion approaches with different thermal energies. Moreover, the relationship between mechanical properties and the crystal structure, alpha:beta-phase ratio, was characterized systematically to evaluate the samples produced via these two powder bed methods. The corrected beta-phase fractions of the EBM and SLM specimens were 0.12 and 0.10, respectively, which corresponded to a slight difference in mechanical strength. Furthermore, the EBM- and SLM-fabricated specimens presented excellent biocompatibility in an in vitro cellular evaluation. Consequently, our findings demonstrated that the AM-fabricated Ti6Al4V parts conformed to all of the international standard requirements, particularly in terms of the mechanical properties, chemical composition, and non-corrosiveness. Thus, we believe that our study can contribute to the further development of additive manufacturing processes.