Investigation of laminated fabric cages used in rolling bearings by ToF-SIMS

Properties of textile-laminated phenolic composition cages were studied by ToF-SIMS: (i) by monitoring the di-octyl-sebacate (DOS) content of the lubricant film within the elastohydrodynamic (EHD) contact region of the inner and outer rings of tested high-speed rolling element bearings, and (ii) by the investigation of boundary layers of cages in the region of the cage–ball-contact. Portions of the DOS amount stored in the cage by the bearing conservation process are released vs. the operation time via the cage surfaces into the EHD contact regions. revealed that the amount of the diester DOS separated from the cage into lubricating film of the raceway, is influenced by the lubricant additive formulations used in the tribological tests via their attributes concerning the acting tribological system processes like wear, boundary layer formation, adsorption, etc. ToF-SIMS research [1,2] of both the lubricant surface and the boundary layer in the EHD contact region showed that the primary antioxidants used as additives do not only act as oxidation inhibitors, but that they also do influence the wear processes of the counteracting bodies and the formation processes of boundary layers on rolling bearing steel SAE 52100. he amounts of DOS, found in dependence on six different lubricant additive formulations A–F investigated, also an influence on the boundary layer formation processes is detected for the surface of the textile-laminated phenolic composition cage. ToF-SIMS imaging and depth profiling of cage boundary layers prove this dependence of the boundary layer formation process. condary ion (SI) intensities of DOS correspond with the lubricant dependence of the 56 Fe + / C 4 H 8 + ratios obtained from the used lubricant films in the EHD contact regions [1,3] as well as with the ratios 56 Fe + / C 4 H 8 + of the boundary layers in the raceways and of the cages [3]. Both the 56 Fe + / C 4 H 8 + ratios and the DOS intensity values show an indirect dependence to the lubricant service life of the lubricants A–F.