Characteristic of oxide layers obtained on titanium in the process of thermal oxidation

Abstract

Thermal oxidation in air may be one method to improve the properties of titanium and its alloys through its influence on the structure and properties of the material's surface layer. This paper presents a description of oxide layers obtained on the surface of Grade 2 titanium as a result of oxidation at temperatures of 600 and 700°C. On the basis of kinetic curves, it was found that the intensity of oxide layer growth increased with oxidation temperature. Studies of the surface morphology of oxide layers showed that the size of the formed oxide particles was greater following oxidation at 600°C. The obtained layers were subjected to X-ray phase analysis and microhardness measurements. Irrespective of oxidation temperature, the scale consisted of TiO2 oxide in the crystallographic form of rutile and of Ti3O oxide. The hardness of oxide layers amounted to around 1265 HV and was more than 4 times higher compared to the material in its initial state.