Evading stability-biocompatibility tradeoff in TiNb coatings with armour-like super hydrophilic micro-nano structure surface

Modification of micro-nano structures on the surface of medical implants using a femtosecond laser (FSL) can improve cell behavior, increase tissue and material bonding strength, and promote preferred osseointegration. Nevertheless, the FSL processed micronano structures suffer from a compromise between biocompatibility and structural stability. Herein, a Ti32$5Nb alloy laser cladding (LC) coating was initially created on the surface of the Ti6Al4V (TC4) substrate, followed by the construction of an armour-like micro-nano structure with structural stability and biocompatibility on the coating surface. The results show that the microhardness, were resistance and corrosion resistance of the coatings were significantly improved. It efficiently prevents wear damage to the micronano structure by modifying the surface armour structure of FSL. In addition, a considerable quantity of hydroxyapatite (HA) is deposited on the surface, resulting in a Ca/P ratio that is closer to that of osteogenesis. Moreover, the surface structure is a periodic micronano structure with three-level distribution, which can guide the migration and proliferation of cell nanofiber matrix. Human osteosarcoma cells (MG-63) adhere to the surface and proliferate rapidly along the direction of the micro-nano structure. Hereby, the armoured micro-nano structures developed exhibit sustained wear resistance and great biocompatibility. It offers a wide range of applications in the field of surface modification of orthopedic biomaterials.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Modification of micro-nano structures on medical implants using a femtosecond laser can enhance cell behavior, bonding strength, and osseointegration. However, the compromise between biocompatibility and structural stability is a challenge. In this study, a Ti32$5Nb alloy laser cladding coating was created on a Ti6Al4V substrate, followed by the formation of an armor-like micro-nano structure with improved properties. The results show enhanced hardness, wear resistance, and corrosion resistance of the coatings. Additionally, the surface structure promotes cell migration and proliferation, and the deposition of hydroxyapatite enhances biocompatibility.