A.M. Oliveira, A. Garcia, D.E. Hirayama, H.B. Antonoff, M.A. Mendonça, S.S. Gomes, K.L. Guimarães
Institute for Technological Research of State of São Paulo,
Keywords: nanolubricant, nanoparticles, graphite
Summary:Additives are commonly used in lubricating fluids in order to modify properties aimed at improvement of their technical performance. Such fluids can suffer when exposed to temperature changes, and these changes may reflect in loss of important properties to promote a good lubrication. Applying the study of kinetics of degradation, can analyze the thermal decomposition of lubricants, allowing analyzing the effects of additives on lubricating fluid formulation. To this end, formulated using the method of high energy dispersal, a nanolubricant composed of a base oil SAE 20W50 classification and graphite medium nanoparticles radius 400-450 nm. Such particles were analyzed about their physical chemical aspects and the nanolubricant raised with regard to viscosity. After this preliminary step of characterization, the modified nanolubricant with nanografhite was subjected to a study of kinetics of degradation, with the use of the technique of thermogravimetry (TG). It is observed that the high temperature the oil additive with nanoparticles takes longer to degrade, as compared with the base oil. Analyzing the predetermined maximum temperature for the kinetic study of the 400° C, temperature at which it was possible to scan the results of 20% degradation to 100% in mass loss for both samples studied, has been that for the base oil, the time for thermal degradation of 20%, 40%, 60%, 80% and 100% of the sample were 0, 27 min, 0, 58 min , 1, 02 min, 1, 80 min and min respectively, as 480.00. For the nanolubricant sample containing graphite nanoparticles, analyzing the study conducted in the same manner in which it assessed the results obtained for the sample of base oil, an increase in the time required for the thermal degradation of 20%, 40%, 60%, 80% and 100% of the sample, being that time 0, 56 min, 1, 28 Min, 2, 29 min, 4, 02 min, and 480, 00 min respectively, double the amount provided by the study of base oil 20w50 , leading to realization of the real thermal modification of lubricant with the addition of graphite nanoparticles, influencing on heat resistance.