Abstract:
To enhance compatibility with the mechanical properties of human bone, promote osteoblast growth and mitigate the stress shielding effect, a femtosecond laser was used to fabricate a ring-shaped microporous structure on the surface of TC4 titanium alloy. The influence of this structure on cellular biocompatibility was investigated. The surface morphology characteristics were examined by scanning electron microscopy (SEM), the phase composition was analyzed by X-ray diffraction, surface roughness and three-dimensional morphology were evaluated through laser confocal microscopy, and the wettability of the sample was characterized via contact angle measurements. The findings indicate that the phase composition remains essentially unchanged after processing. The titanium alloy surface exhibits a raised circular structure with dense micropores distributed along the ring edges. The overall surface roughness is 3.643 μm. A height difference exists between the transverse and longitudinal cross-sections at the ring edge and the center, and the hydrophilicity of the material is significantly enhanced. Cell tests show that compared with unprocessed TC4 titanium alloy, samples with microporous structures exhibit greater cell adhesion, faster cell proliferation and favorable cell morphology on their surfaces. In conclusion, the annular microporous structure fabricated on TC4 surfaces by femtosecond laser processing improves cellular biocompatibility merely by altering surface topography without changing phase composition. This provides a new strategy for the application of TC4 titanium alloy in biomedical fields.