The friction and wear characteristics and lubrication mechanism of imidazole phosphate ionic liquid

Several imidazole phosphate ionic liquids with varying carbon chain length have been synthesized at room temperature. Corrosion characteristics and tribological properties of these synthesized ionic liquids were studied using four-ball friction and wear testing machine. Its lubrication mechanism was also investigated by means of electron microscopy and X-ray photoelectron spectroscopy. The experimental results showed that no corrosion was generated when the imidazole phosphate ionic liquid was applied to steel-steel pair. Meanwhile, the imidazole phosphate showed excellent anti-wear and lubricating performances, its frictional performance was related to the polarity of ionic liquids. It is suggested that the ionic liquids react with friction surface to form a protective film of iron phosphate and result in reduction in friction and wear.