Wear properties of CP-Ti after surface functionalization with Direct Laser Interference Patterning

In this work, the tribological properties of pure titanium functionalized using Direct Laser Interference Patterning (DLIP) with two types of patterns (grooves and grid) have been evaluated with comparison to the initial state (shot-peened+acid-etched). Tribological tests were carried out in Hank’s solution at 37 °C, using the pin-on-plate method. The main aim of this study was to investigate the effect of surface patterns on wear behavior. Samples with more uniform surface topography — initial state and DLIP grid — exhibit similar wear behavior. Both the Initial state and the DLIP grid, for all examined samples, displayed smooth wear curves, whereas the DLIP grooves showed stepped wear processes, for both investigated directions. The anisotropic surface topography of DLIP grooves significantly affects the sedimentation and deposition of wear residues. The progressive accumulation of the wear products in the contact zone causes a decrease in the displacement curve of the pin/plate couple. After reaching the critical thickness, wear residues detached, leading to a sudden jump in the displacement curve of several micrometers in height. Despite DLIP functionalization, the wear behavior remained strongly influenced by the crater topography formed during shot peening before laser functionalization. • DLIP-treated surfaces exhibit periodic and multimodal surface roughness. • Surface topography affects the resulting wear mechanisms. • Topographic features play the most significant role in the wear process.