Surface investigation of lubricant–metal interactions by synchrotron photoemission spectroscopy

Synchrotron radiation X-ray photoemission spectroscopy has been used to study wear tracks produced during tribological tests on steel specimens. This was a successful feasibility test for the use of ultrabright synchrotron radiation in tribology. We found that the resulting high flux and small spot dimensions on a sample of 100×30 μm2, are ideal for testing disk samples having circular wear tracks with radius 1 cm and width 250 μm. A photon energy of 350 eV was used to analyse Zn 3d, P 2p, S 2p and C 1s peaks on samples produced in different conditions.