Fretting Wear Behavior of Ti-6Al-4V With Grid-Like Surface Textures: Debris-Mediated Mechanisms and Regime Transition Control

Abstract Laser-fabricated grid-like textures were introduced on Ti-6Al-4V flats to quantify their influence on fretting performance under variable normal loads (20–100 N) and a fixed displacement amplitude of 40 µm. Using a ball-on-flat configuration (105 cycles, 100 Hz), the evolution of friction, system deformation, and maximum wear depth was correlated with high-resolution wear scar topography and debris distribution. In the gross slip regime (20–60 N), deeper and denser grids (≈40 µm depth, 140 µm pitch) entrapped a compliant debris layer that reduced maximum wear depth by up to 35% compared with untextured controls, even after the central texture had been erased. The same textures shifted the partial slip threshold to lower loads (≈60 N) by locally accommodating displacement and moderating shear. In near-stick conditions (80–100 N), however, deep grids promoted plastic indentation and mesa cracking, indicating a trade-off between debris retention and structural integrity. Stable friction coefficients were marginally lowered in gross slip but slightly elevated in partial slip because of increased adhesive resistance. System deformation saturated beyond 80 N; the deepest grid (T3) exhibited the lowest stabilized value in partial slip, corroborating its superior elastic accommodation. The results demonstrate that grid-like surface textures provide a robust route to mitigate fretting wear of Ti-6Al-4V provided groove depth and density are optimized to balance debris storage, load-bearing capacity, and resistance to texture fracture.