Spectromicroscopy of tribological films from engine oil additives. Part I. Films from ZDDP's

摘要: Antiwear films formed from pure neutral alkyl‐ and aryl‐ZDDP's, a commercial ZDDP, have been studied with high resolution synchrotron‐based photoemission spectromicroscopy new instrument, MEPHISTO. Good P L‐edge XANES spectra taken on areas between 12 400 μm2, good images of phosphates ZDDP obtained at ∼1 μm both smooth rough steel. These spectra, corresponding images, show immediately that the chemistry morphology alkyl aryl are very different. The film contains range smaller larger protective polyphosphate pads few to ∼25 μm2 in area. We shown small large contain long chain polyphosphate; while short polyphosphate. ortho‐ or pyro‐phosphates, much thinner more uniform, obviously streaking initial wear, no obvious pad formation. generated rubbed base oil, is converted pyro‐phosphate, but amount distribution phosphate does not change noticeably. antiwear remarkably stable physically.