Yu Xie, Lei Li
Titanium alloys are widely used in aerospace, marine engineering, and biomedical fields owing to their excellent specific strength, corrosion resistance, and biocompatibility. As an important surface modification technique, sandblasting combined with acid pickling can not only eliminate the machining defects in Ti-6Al-4V but also improve its surface morphology, thereby playing a crucial role in enhancing its service performance. By employing advanced characterization equipment, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), a 3D profilometer, and a friction and wear tester, combined with wetting theoretical models and morphological evolution analysis, this study systematically investigated the comprehensive effects of different pressure sandblasting followed by acid pickling on the surface microstructure, wetting behavior, and tribological properties of forged Ti-6Al-4V alloy. The results indicated that the combined application of sandblasting and acid pickling exerted a significant regulatory effect on the surface and interface characteristics of the Ti-6Al-4V alloy. After the combined sandblasting and acid pickling treatment, a distinct micro-pit network structure was formed on the surface of the Ti-6Al-4V alloy, and its hydrophilicity and roughness showed a positive correlation with the increase in sandblasting pressure. Notably, the microstructural evolution exhibited a high degree of internal consistency with the macroscopic wear resistance: the hierarchical micro-pit network exposed after acid pickling exerted an excellent "debris capture" effect, thereby suppressing the severe third-body abrasive wear observed in the solely sandblasted state. This study aims to enhance the surface roughness, wear resistance, and hydrophilicity of the Ti-6Al-4V alloy, providing a cost-effective and industrially applicable method for the surface texturing of titanium alloys.