Influence of Oxidation Processing Temperature on the Structure, Mechanical and Tribological Properties of Titanium Using Carbon Sheets

Abstract

Surface processing of pure titanium was performed using a carbon sheet to increase the surface hardness and improve tribological property. The effect of processing temperature (750–950 °C) for 2 h on the structure, mechanical and room-temperature tribological properties of the treated samples was investigated using X-ray diffraction, scanning electron microscopy, and ball-on-disk tribometry, respectively. The Gibbs free energy was also calculated to evaluate the compounds generated at different processing temperatures. As a result of the examination, the hardened layer was mainly composed of titanium oxide and titanium carbide. With the increasing processing temperatures, the thickness of the hardened layer increased first and then decreased gradually. It was also revealed that the surface hardness was increased first and then decreased as the processing temperature increased. The fricative value of the treated samples showed a minimum value of 84.1 dB for a processing temperature of 850 °C. The depth and width of the wear tracks increased first and then decreased gradually with the increasing processing temperatures. The worn surface of the treated samples at higher temperatures showed a very good wear resistance. A processing temperature at 850 °C is considered optimal as it provides sufficiently high hardness and a low coefficient of friction to reduce fricative during practical use.