Surface engineering of additively manufactured Ti-6Al-4V alloys: A comparative study on micro/nanoscale topographies for biomedical applications

This study investigates the generating micro/nanoscale topographies surface texture and comparison of their bioactivity performance on Ti-6Al-4V alloys fabricated using DMLS and EBM methods for potential biomaterial applications. To achieve the desired micro/nanoscale roughness, the EBM and DMLS samples underwent a sequence of sandblasting (S), acid-etching (E) and anodization (A), resulting in SEA-treated surfaces. The modified alloys were then analysed and characterized in terms of their microstructure, surface roughness, topography, and wettability. Furthermore, cell culture experiments were performed in vitro to assess the bioactivity of these surfaces. SEM images showed that both EBM and DMLS samples exhibited micro/nanoscale morphology and topography. After surface modification, the Ra surface roughness values were calculated to be approximately 0.86 mu m for the EBM sample and 0.76 mu m for the DMLS sample. The contact angle measurements indicated that the EBM sample had a contact angle of 37.55 degrees, while the DMLS sample had a contact angle of 19.24 degrees after undergoing SEA treatment. HOB cell viability on the SEA-treated surfaces was found to be 97.03 % for the DMLS sample and 93.80 % for the EBM sample after 72 h. Throughout the incubation period, the HOB cells were observed to attach and spread out on the surfaces of both the DMLS and EBM samples.