Effect Of Ti-Basd Nanoparticles On The Lubricating Oil Properties And Its Application In Engines

In recent years, with the rapid development of nanotechnology research, large numbers of attenations had been attacted on the research of nanometer materials in lubricating oil field. As lubricating additives, nanometer particles have unique physicochemical properties and excellent tribological characteristics, such as small size, large surface area, and an excellent effect of lubrication and self-healing could be obtained. Due to the unique properities of the nanoparticles, it has made great significance to carry out research and development on the high-performance nanometer lubricating additives.In this paper, the tribological properties of three types of Ti-basd nanoparticles in lubricating oil (as additives) had been investigated, as well as the properties of anti-friction and self-healing. The best content of the Ti-basd nanoparticles has been chosed to apply on a certain type of diesel engine test bench. The main results of this paper are as follows:1) The experiments of the stability of Ti-basd nanoparticles in lubricating oil were carried out by using different concentrations of dispersant (PEG-200). It showed that if the ratio of the titanium nanoparticles (0.5%) and dispersant (1.0%) is 1/2, a stable composite lubricating oil system can be obtained.2) The tribological behaviors and self-repairing mechanism of different nanometer lubricating oil additive TiN, TiO2 and TiC were investigated in different working conditions using four-ball testing machine. Experimental results showed that the wear resistance and self-healing performance are different under the conditions of different Ti-basd nanoparticles, loads and rotational speeds. Ti-basd nanoparticles can reduce surface roughness siginificantly, which is useful to reduce the surface wear. Meanwhile the self-healing performance of the Ti-basd nanoparticles siginificantly improves the anti-friction properties of oil-based lubricant. The best anti-fricition propties can be obtained when the masses of the titanium nanoparticles are setted as 0.5%. Among them, the TiN has the best wear resistance and self-healing property. 3) The experiments of the base oil containing Ti-basd nanoparticles (mass of 0.5%) had been carried on a certain type of diesel engine test bench (4JB1 diesel engine) to investigate the external characteristics of the engine by measuring the engine power, torque and fuel consumption. By using the lubricating oil with Ti-basd nanoparticles, the friction coefficient and the friction power can be reduced, the engine's power and torque can be improved, and the fuel consumption rate can be significantly reduced as well. On the other hand, a repair layer will be formed gradually by the additives of lubricating oil on the sealing surface of the piston rings, also the reduction of the amount of the mixed gas that of appropriate proportion and get into the crankcase can significantly improve the cylinder pressure. Cylinder pressure is the main factor which affects the fuel consumption:the bigger the cylinder pressure is, the faster the burning speed of the mixed gas is, the less the loss which were taken away by cooling water and waste gases is, and a better engine power and economic performance can be obtained.