Tribological Performance of Charged Vegetable Lubricants

A vegetable lubricants suited for electrostatic spraying lubrication was prepared by modifying LB-2000 vegetable lubricants with surfactant sodium dodecyl benzene sulfonate(SDBS). The molecular structure of charged vegetable lubricants was characterized by Fourier Transform infrared spectroscopy, the charge property and physicochemical properties were analyzed. The tribological performance of vegetable lubricants on electrostatic spraying lubrication was investigated by using a four-ball tester. The morphology and main elements of the worn surfaces of the steel ball were characterized by microscope and X-ray photoelectron spectroscopy, respectively. The results indicate that the polarity of vegetable lubricants molecule was increased after holding the same electric charge, while the dynamic viscosity, contact angle and surface tension of vegetable lubricants were reduced. In addition, the active particles O₃, O formed by corona charge accelerated the oxidation of fresh surface. The adsorption film and oxide film contributed to the formation of lubricating film on the friction interface and therefore the anti-wear and anti-friction of the charged vegetable lubricants were improved.