EFFECT OF IRON MICRO-/NANO-PARTICLE ADDITIVES ON TRIBOLOGICAL BEHAVIOR OF LUBRICATING OILS

Nowadays, many attempts are made to solve tribological problems by the introduction of metallic and non-metallic nanopowders as lubricant additives. The aim of this work is a synthesis of iron nano-/microparticles using inverse micelles technique in commercially available mineral and rapeseed oils that are served as a nonaqueous phase. The effect of obtained iron nano-/microparticles (0.1 wt%) on the tribological properties of lubricating oils is investigated under variable load, sliding speed and type of bi-directional sliding conditions using MUST tester. In the bi-directional tests, the addition of surfactants/Fe particles has no effect on the friction behaviour of the untreated rapeseed oil. For mineral oil an increase in coefficient of friction and wear was noticed, that is attributed to the abrasive activity of the iron particles settled down in the absence of agitation. Some corrosion products were noticed on the disk with mineral oil/OS-20 based suspensions, and need further investigations. The advantages of four ball technique against MUST is discussed.