Tribological Performance of Crosshatch Pattern Textured and Heat Treated Dual Engineered Ti6Al4V Surface under Bio-Lubricated Line Contact Configuration

This study combines the laser surface texturing technology and heat treatment process to fabricate a dual surface engineered Ti6Al4V consisting of micro-groove crosshatch pattern texture covered with hard TiO2 oxide coating to reduced friction and improve the wear resistance at the bio-lubricated interface. Crosshatch texture with 25 µm width, 5 µm depth at 25% area density were fabricated using nanosecond Nd:YAG laser over Ti6Al4V surface and then heat treated at 600 ºC for 48 hours. XRD result showed rutile TiO2 phase formation along with the presence of anatase TiO2, Al2O3 and Ti3O minor phases whereas, the surface hardness was increased to 1538±41 HV. Bio-tribology experiments were carried out for 45 and 90 º oriented micro-groove crosshatch textures, with and without heat treatment, under partially replicating hip implant articulation. Results demonstrated 60% friction reduction corresponding to the 45 º oriented crosshatch texture with heat treatment. Further, the worn-out surface morphology showed reduced wear damage and good wear debris entrapment inside the micro-grooves.