Temperature effets on mechanical properties of zinc dithiophosphate tribolfilms

Karim Demmou (1) , Sandrine Bec (1) , Jean-Luc Loubet (1) , Jean-Michel Martin (1)

1 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes

Nanoindentation tests were performed at several temperatures (24 to 80°C) on one antiwear zinc dialkyl-dithiophosphate (ZDTP) tribofilm using a Nanoindenter XP® entirely set into a climatic chamber. Mechanical properties of the tribofilm were determined using a simple model. AFM observations were conducted to estimate the order of magnitude of the film's thickness. The effect of applied pressure on the elastic properties was demonstrated and taken into account in the present analysis. The use of the F/S² parameter, independent of contact geometry, revealed a hardness dependency upon temperature. Furthermore, careful AFM observations of the residual pile-up produced by plastic flow around the indents pointed out the evolution of the film deformation process with temperature.

Mots clés: Nanoindentation; Zinc Dialkyl-ditihiophosphate; ZDTP; Tribofilm; Temperature effects

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Karim Demmou, Sandrine Bec, Jean-Luc Loubet, Jean-Michel Martin. Temperature effets on mechanical properties of zinc dithiophosphate tribolfilms. Tribology International, 2006, Publié dans Tribology International, volume 39 (12), 39, pp.1558-1563. ⟨10.1016/j.triboint.2006.01.025⟩. ⟨hal-00110924⟩