EFFECT OF LUBRICANT ADDITIVES ON GEAR MICRO-PITTING

Abstract

Abstract: A new method was developed to identify and evaluate the micro-pitting corrosion of gears by mini-traction machine (MTM), focused ion beam (FIB), scanning electron microscope (SEM), transmission electron microscope (TEM) and energy dispersive spectrometer (EDS). It was found that friction-reduction and anti-wear properties of additives were the key factors affecting micro-pitting resistance. In the MTM test, there was an area where micro-pitting was easy to occur with friction track width of no greater than 400 μm and friction coefficient of no less than 0.097. The development of additives and formulations should avoid this area and comprehensively balance friction-reduction and anti-wear properties. The better the anti-wear property of the friction film formed by the additive, the narrower the friction track of MTM, the more concentrated the stress, and the easier to produce the micro-pitting corrosion in the MTM test. The anti-micro-pitting performance can be improved by adding additives which can reduce the friction coefficient of the system.

Key words: micro-pitting, focused ion beam, additives, friction, stress

References

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