Akademik Veri Yönetim Sistemi
5th International Conference of Materials and Engineering Technology (TICMET'23), Trabzon, Türkiye, 13 - 16 Kasım 2023, ss.431
Ultra-high molecular weight polyethylene (UHMWPE) is the most commonly preferred bearing material against ceramic or metallic counterparts in total hip replacement prosthesis due to its excellent combination of mechanical properties, biocompatibility and wear resistance.
Even though these superior features, the service life of total hip replacement prosthesis is usually 10-15 years with some exception of 20 years or more. The main reason for this is the wear of UHMWPE or metallic components in the prosthesis. Therefore, increased service life of the prosthesis is utmost concern. To overcome this, surfaces of UHMWPE materials can be laser textured to form semi-spherical cavities that acts as lubricant pockets, and reduce friction and eventually the wear. This study aimed to reveal the effects of surface texturing via different laser sources (nanosecond and femtosecond lasers) on the three different medical grade UHMWPE materials, namely cross-linked polyethylene GUR 1020 XL, cross-linked vitamin E added polyethylene GUR 1020 EXL, and standard polyethylene all by means of block-on-disk friction tests against Ti6Al4V disk material.
Femto-second laser surface texturing was applied at HiLASE Centre of Czech Republic via CARBIDE CB-3-40W (Light Conversion, Vilnius, Latvia) femrosecond laser system and repeatable cavities were formed successfully (Figure 1). The cavities were formed in three different areal density (5, 10, 15%), three different cavity depth (30, 40, 50 μm), and three different cavity diameter (40, 100, 150 μm). Friction tests were performed with a custom made tribotester available at the Department of Mechanical Engineering of Karadeniz Technical University. Bovine serum was used as lubricant at the contact interface. Tests last 40 minutes which equivalent of 3000 m sliding distance under 150 N loading which corresponds to 1 MPa contact pressure, and with a sliding speed of 1.5 m/s.