The tribological performance of a long chain alkyl phenylboric ammonium derivative and its interaction with ZDDP

Abstract

A long chain alkyl phenylboric ammonium derivative (DBBM) was synthesized as a lubricating additive. The tribological performances of DBBM and combinations of DBBM and ZDDP as additives were evaluated, which suggests that DBBM has better tribological properties than ZDDP. X-ray absorption near edge structure spectroscopy was used for the analysis of thermal films and tribofilms. The results indicate that the boron in additive mainly forms trigonal and tetrahedral coordination boron both in thermal films and tribofilms, while sulfur mainly generates iron sulfate in thermal films and iron sulfide, iron disulfide, and iron sulfate in tribofilms. It also can be found that it is more likely to form low valence sulfur when the concentration of ZDDP increases in the combinations.