title: Tribological and thermal stability study of nanoporous amorphous boron carbide films prepared by pulsed plasma chemical vapor deposition.
abstract: In this work, the thermal stability and the oxidation and tribological behavior of nanoporousa-BC:H films are studied and compared with those in conventional diamond-like carbon (DLC) films.a-BC:H films were deposited by pulsed plasma chemical vapor deposition using B(CH3)3gas as the boron source. A DLC interlayer was used to prevent thea-BC:H film delamination produced by oxidation. Thermal stability ofa-BC:H films, with no delamination signs after annealing at 500 °C for 1 h, is better than that of the DLC films, which completely disappeared under the same conditions. Tribological test results indicate that thea-BC:H films, even with lower nanoindentation hardness than the DLC films, show an excellent boundary oil lubricated behavior, with lower friction coefficient and reduce the wear rate of counter materials than those on the DLC film. The good materials properties such as low modulus of elasticity and the formation of micropores from the original nanopores during boundary regimes explain this better performance. Results show that porousa-BC:H films may be an alternative for segmented DLC films in applications where severe tribological conditions and complex shapes exist, so surface patterning is unfeasible.
authors.affiliation: Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology, 2-12-1O-Okayama, Meguro-ku, Tokyo, 152-8552, Japan; Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Shahira
authors.initials: S
authors.lastname: Liza
authors.affiliation: Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology, 2-12-1O-Okayama, Meguro-ku, Tokyo, 152-8552, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Ohtake
authors.affiliation: Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology, 2-12-1O-Okayama, Meguro-ku, Tokyo, 152-8552, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Akasaka
authors.affiliation: Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology, 2-12-1O-Okayama, Meguro-ku, Tokyo, 152-8552, Japan; Mechanical Engineering Department, Universidad Politécnica de Madrid, C/José Gutiérrez Abascal, 2, E-28006 Madrid, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Munoz-Guijosa
keywords: boron carbide film; lubrication; porous surface; thin film; tribology