Although the lubrication systems for internal combustion engines have been designed to prevent engine wear and friction, their configuration does not contemplate the maximum use of each load of lubricant; because of this limitation, lubricant consumption is currently an environmental and economic problem. In this work, the performance of lubrication systems to form the tribological film that prevents wear is simulated and optimized, through the mass balance of the lubricant precursors contained in the oil and the implementation of optimal control techniques. Optimization results indicate that regulating the flow of lubricant passing through the engine prevents excessive degradation of lubricant precursors, maximizing the life of each lube oil charge, giving the possibility to increase the sustainability of internal combustion engines.

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Nanocharacterization of titanium nitride thin films obtained by reactive magnetron sputtering V V Merie, M S Pustan, C Bîrleanu et al. Abstract. TiAlNO coatings were obtained on corning glass by means of the co-sputtering technique. Two series were fabricated. In the first one the argon flux was maintained at 12 sccm, while the nitrogen flux was varied in 3, 6 and 9 sccm; in the second one the argon flux was 15 sccm and the nitrogen flux was varied in 2, 3, 4, 5 and 6 sccm, which produced a working pressure variation. For co-sputtering in the first series, three targets were occupied: titanium, alumina and aluminium; meanwhile in the second series, two targets were used: titanium monoxide and aluminium plus an amount of titanium, specifically, 3.5 gr in the aluminium target, occupying 40% of the total effective area of the target. Structural, mechanical and electrical properties were obtained through X-ray diffraction, the Vickers microhardness test and resistivity probes, respectively. For first series, X-ray diffraction detected titanium nitride (TiN) in the crystalline phase; for the second series, aluminium nitride and titanium oxide (TiO) 3.38 . The difference in the crystalline structure obtained for the series explains the microhardness values; in the first series a maximum value of 20.4 GPa at 2 sccm of nitrogen was obtained, whereas in the second series the maximum value obtained was 8 GPa. As one can observe, the increase in nitrogen flux is not an advantage to hardness, but in electrical resistivity it has a positive effect. The results suggest that TiAlNO is versatile material that could be used for both mechanical and electronic applications; however, it is important to control fabrication conditions.