BIOMASS CARBONS AS ADDITIVES FOR LUBRICATION: FRICTION REDUCTION KEY PARAMETERS

Abstract

International audienceIn boundary lubrication regime, friction reduction and antiwear processes are associated to the presence of additives in the lubricating oils or greases. These processes are due to the formation of protective tribofilms resulting from chemical reactions between the additives and the sliding surfaces, in the physico-chemical conditions of the sliding contact. But the main problems encountered with conventional additives (transition metal dithiophosphates or carbamates) are their inefficiency in the case of non metallic surfaces and the film formation period (induction period), in which the contacting surfaces undergo sever wear. Recently developed lubrication strategies consist in the use of dispersion in oils of nano additives able to build the protective tribofilm in the sliding contact without reaction with the surfaces [1]. We pointed out in previous studies the good friction reduction properties of various (nano) carbon materials [2, 3]. This work is concerned with the use of activated carbons synthetized from biomass as new additives for lubricants. Special attention is paid to the role of the carbon structure, in terms of morphology, size, (nano)structuration, porosity of the carbon particles on the friction properties of the additives. 1 Mansot, J.L, et al, Brazil