Characteristics of the tribological properties of oxide layers obtained via thermal oxidation on titanium Grade 2

Abstract

Thermal oxidation is an effective technique for modifying the surface of titanium and its alloys in order to improve their poor tribological properties. This paper presents the results of tests concerning titanium Grade 2 subjected to thermal oxidation at 600 ℃ and 700 ℃ for 72 h. The morphology of the surface of the formed oxide scale was determined. The surface of a specimen oxidised at 600 ℃ was unevenly covered by very fine oxide particles. Raising the temperature to 700 ℃ made it possible to cover the entire examined surface with an oxide layer. The obtained scale was characterised by the presence of large irregularly shaped agglomerated oxide particles. Tribological tests showed that the presence of an oxide layer on the surface of titanium significantly improved the resistance of the interacting tribological couple to sliding wear. The obtained 3D isometric images of the trace of wear showed that the formed traces differed in terms of width, depth and shape. It was shown that the area of the cross section of the trace of wear decreased as the temperature of thermal oxidation increased. Scanning electron microscopic observations of traces of wear formed following tribological interaction with an Al2O3 ball showed, in a non-oxidised specimen and a specimen oxidised at 600 ℃, the presence of alternating morphologically varied areas formed as a result of corrugation wear. The oxide layer obtained at 700 ℃ has the highest resistance to sliding wear and completely eliminates the adverse corrugation wear phenomenon.

Influence of laser beam process parameters on the bending ability of Ti-6Al-4V titanium alloy sheets

“…Thus, the presence of a consistent oxide layer over the surface of the substrate after laser irradiation can be observed. The same surface morphology phenomenon due to the thermal oxidation process was also observed in previous studies related to the thermal oxidation of pure titanium and Ti-6Al-4V alloy [35]- [37]. According to previous reports, thermally oxidized Ti-6Al-4V shows better corrosion resistance, higher friction coe cient, mechanical properties, and tribological properties.…”

A Novel Treatment to Selectively Harden Ti6Al4V Surfaces

“…The CoF started low for the TO surface, and it increased steadily with the increment of the tribotest till 0.45 in the end which might be attributed to the thin oxide layer (1−2 μm) worn through at about 700 cycles. 17,24 For the SOD sample, the CoF was higher in the first part of the test which might be caused by the remaining powders on the surface, and it slightly reduced after half of the test cycles, and the change in the CoF was in a narrow range. The sample SOD + TO had a low CoF in the beginning and increased slightly but remained low and relatively stable under 0.2 in the whole process.…”

Effect of the incorporation of carbon in the structure of TiO2 anodized with HCl on the mechanical and tribological properties

“…• Distance radius: 2 mm • Workload: 1 N • Linear speed: 0.1 cm/s • Humidity: 40 ± 2% • Temperature: 26 ± 2 °C A 6 mm diameter alumina ball was used [16].…”