Tribochemical reactions in cold rolling : a ToF-SIMS study of the chemisorption of the lubricant additives on the sheet

Abstract

La chimisorption des additifs de lubrifiant de laminage à froid sur un acier et un alliage d'aluminium est étudiée par spectrométrie de masse ToF-SIMS. L'étude préparatoire de l'adsorption des divers additifs permet de mettre en évidence leur rôle individuel, les compétitions d'adsorption, les seuils thermiques de désorption ou de décomposition. Ces résultats sont confrontés positivement à des essais sur laminoir pilote.

Application of ToF-SIMS surface analysis to tribochemistry in metal forming processes

“…Tests have been performed with partially formulated versions of this lubricant; analyses have been made after strip dipping, PSCT and rolling. Some of the results are described hereafter [16,25,26].…”

“…Here, tests are performed at increasing speed under a constant reduction (40%). Displayed are [16,25]:…”

“…However, the amount of information is still enormous and has to be lumped to be usable. To do this, the following procedure has been evolved [15,16]:…”

“…This required the development of specific data analysis techniques to extract useful information from the huge number of peaks present in the mass spectra [15,16]. This methodological effort is described in the following, together with some tribochemical results.…”

DFT – Modeling of the Reaction of a Polysulfur Extreme-Pressure Lubricant Additive on Iron Surface

“…Several papers report on comparisons of the tribological efficiency of organosulfur additives as a function of number of sulfur atoms, alkyl-or aryl-chains [1]. In tribotests, involving ferrous materials and S-containing additives, the formation of the FeS x compound has been detected in superficial layers by different surface analysis techniques [2,3]. FeS, also known as troilite, has a layered hexagonal structure, low shear strength and high melting point (1100°C), so it is an effective solid lubricant like graphite and MoS 2 [4].…”