Formation of interfacial molybdenum carbide for DLC lubricated by MoDTC: Origin of wear mechanism

M. de Feo , Maria-Isabel De Barros Bouchet (1) , C. Minfray (1) , C. Esnouf (2) , T. Le Mogne (1) , Frédéric Meunier (3) , L. Yang (4) , B. Thiebaut (5) , S. Pavan , J.M. Martin (6)

1 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes
2 MATEIS - Matériaux, ingénierie et science [Villeurbanne]
3 ING - IRCELYON-Ingéniérie, du matériau au réacteur
4 Laboratory of Natural Products Pesticides, College of Plant Protection
5 Total
6 LAGEP - Laboratoire d'automatique et de génie des procédés

A large amount of research has been devoted to the effect of molybdenum dithiocarbamate (MoDTC) additives on the lubricating performances of carbon-based coatings, showing that a high wear rate is produced when the MoDTC is blended with the base oil. However, the mechanisms leading to the coating removal are not fully understood yet. In this work, the friction and wear performances of an amorphous hydrogenated DLC coating doped with silicon and oxygen have been analysed when lubricated by MoDTC-containing oils. Tribological experiments have been conducted with DLC/steel and DLC/DLC contacts under boundary lubrication conditions using a ball-on-flat tribometer. To understand the wear mechanism, the chemical composition of the tribofilm formed on the steel ball counterpart was investigated by X-ray Photoelectron Spectroscopy (XPS). Transmission Electron Microscopy (TEM) coupled with Energy Dispersive X-Ray Spectroscopy (EDX). A new DLC wear model has been proposed and validated. © 2016 Elsevier B.V.

Mots clés: Additives; Amorphous silicon; Carbides; Carbon; Coatings; Energy dispersive spectroscopy; Friction; High resolution transmission electron microscopy; Lubrication; Transmission electron microscopy; Tribology; Wear of materials; X ray spectroscopy; Boundary lubrication conditions; DLC coatings; Energy dispersive X ray spectroscopy; Friction and wear performance; Friction modifier additives; Molybdenum dithio carbamates; Tribological experiments; Wear mechanisms; X ray photoelectron spectroscopy

Domaines: Matériaux

M. de Feo, Maria-Isabel De Barros Bouchet, C. Minfray, C. Esnouf, T. Le Mogne, et al.. Formation of interfacial molybdenum carbide for DLC lubricated by MoDTC: Origin of wear mechanism. Wear, 2017, 370-371, pp.17-28. ⟨10.1016/j.wear.2016.10.002⟩. ⟨hal-01804244⟩