Premium
Characterization and Tribological Investigation of Sol–Gel Titania and Doped Titania Thin Films
Author(s) -
Zhang Wenguang,
Liu Weimin,
Li Bin,
Mai Guangxin
Publication year - 2002
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.2002.tb00351.x
Subject(s) - materials science , x ray photoelectron spectroscopy , thin film , tribology , composite material , doping , scanning electron microscope , abrasive , abrasion (mechanical) , sol gel , nanotechnology , chemical engineering , optoelectronics , engineering
Titania (TiO 2 ) and doped TiO 2 ceramic thin films were prepared on a glass substrate by a sol–gel and dip‐coating process from specially formulated sols, followed by annealing at 460°C. The morphologies of the original and worn surfaces of the films were analyzed with atomic force microscopy (AFM) and scanning electron microscopy. The chemical compositions of the obtained films were characterized by means of X‐ray photoelectron spectroscopy (XPS). The tribological properties of TiO 2 and doped TiO 2 thin films sliding against Si 3 N 4 ball were evaluated on a one‐way reciprocating friction and wear tester. The AFM analysis shows that the morphologies of the resulting films are very different in nanoscale, which partly accounts for their tribological properties. XPS analysis reveals that the doped elements exist in different states, such as oxide and silicate, and diffusion took place between the film and the glass substrate. TiO 2 films show an excellent ability to reduce friction and resist wear. A friction coefficient as low as 0.18 and a wear life of 2280 sliding passes at 3 N were recorded. Unfortunately, all the doped TiO 2 films are inferior to the TiO 2 films in friction reduction and wear resistance, primarily because of their differences in structures and chemical compositions caused by the doped elements. The wear of the glass is characteristic of brittle fracture and severe abrasion. The wear of the TiO 2 thin film is characteristic of plastic deformation with slight abrasive and fatigue wear. The doped TiO 2 thin films show lower plasticity than the TiO 2 thin film, which leads to large cracks. The propagation of the cracks caused serious fracture and failure of the films.