Development of self-lubricating titania/diamond nanoparticle composite

Diamond nanoparticles synthesised by a detonation method and with average size similar to4 nm have excellent lubricating ability. This study describes the fabrication of TiO2 based matrix composites with dispersed diamond nanoparticles for biomedical applications, and the mechanical properties and friction properties of such composites. The mixing process utilising a sol-gel method achieved a homogeneous mixture between the diamond nanoparticles; and the TiO2 gel. The heating conditions were determined by thermogravimetric analysis (TGA) and differential temperature analysis (DTA). The dried TiO2/diamond nanoparticles composite gel was finely powdered by ball milling and was consolidated at 1073-1273 K by spark plasma sintering. In the fabricated composite, adding diamond content changed the transforming temperature from anatase phase to rutile phase, and the dispersed diamond nanoparticles were chemically stable at this high consolidating temperature. Friction measurements showed that the addition of 1 vol.-% diamond nanoparticles to TiO2 improved the coefficient of friction and wear rate.