Texturization of polycrystalline titanium surfaces after low-energy ion-beam irradiation: Impact on biocompatibility

In this study, the impact of low-energy (1 keV) Ar+ ion-beam irradiation on the morphology of polycrystalline Ti disks was investigated. Targets were prepared by cutting and mechanically polishing commercial rods. The surface topographies before and after irradiation were characterized by scanning electron microscopy (SEM) and mechanical profilometry. Irradiation was performed using a wide range of incident angles (αi) from normal to grazing geometries at a total dose of 1018 ions/cm2. SEM analysis of the irradiated Ti targets revealed clear texturing with various attainable surface morphologies depending on αi. The surface features varied from ripples within patches with fingerprint-like patterns (0 ≤ αi ≤ 60°) to oriented structures parallel to the direction of the ion beam, such as pillar/tip structures (65 ≤ αi ≤ 75°) and shallow ripples (αi ≈ 80°). This morphological selectivity could be attributed to the competitive diffusive and erosive regimes, where the lateral uniformity of the morphology was affected by the limited size of the crystal grains. Finally, the wettability and biocompatibility of the characteristic topographies were evaluated, and the results indicated improved performance of the ion-beam-textured surfaces compared to the untreated ones.