Preparation and surface modification of 3D printed Ti–6Al–4V porous implant

Three-dimensional (3D) printed titanium alloy implants hold enormous potential in orthopedic applications to avoid stress shielding. However, titanium alloy is bioinert, limiting its application and making surface modification a necessity. In this paper, porous implants were treated by acid etching and anodizing to improve the bioactivity, which was evaluated by simulated body fluid (SBF) immersion test. The results showed that, after surface modification, micro–nanocomposite structures were obtained on the titanium surface, and after immersing in SBF for 2 weeks, the implants showed a drastically enhanced apatite forming ability, confirming improved bioactivity. However, the surface structures were different at different positions and it is believed that this phenomenon is closely related to the different current densities of the surfaces during anodic oxidation. Our research evaluates the effect of anodic oxidation at different voltages on the surface modification and provides a reference for improving the bioactivity of the medical porous implant surface prepared by 3D printing.