Friction and wear characteristics of self-lubricating spherical bearings under different stresses

Abstract

In order to study the effect of stresses on the friction and wear properties of self-lubricating spherical plain bearings，the self-lubricating spherical bearings EN2584R12 was taken full life cycle tests under 50%，100% and 150% standard stresses conditions at room temperature according to SAE AS 81820. And the static stress tests of the flat samples with the liner were carried out. The deformation of the liner after static stresses were observed by using three-dimensional white light interference profilometer and optical microscopy. Stereo microscope，optical microscopy and scanning electron microscopy were used to observe the wear morphology and debris morphology of the inner and outer rings after full life swing wear under different stresses. Results show that the self-lubricating liners under three stresses have been worn through，the wear characteristics and friction coefficients of self-lubricating liners under three stresses have no significant difference. As the pressure increases，it is found the temperatures of the bearing surface are higher，the debris are darker and larger，the instability period become earlier，the liner is damaged more quickly. Different stresses have significant effects on the life of bearings. The oscillating wear life under low and medium stress conditions is increased to 17.95 times and 7.86 times compared to high stress conditions，respectively. The wear mechanisms under three stresses are the mixed wear of abrasive wear and adhesive wear. The adhesive wear in the direct pressuring zone increases with the increase of stress，while the abrasive wear in the non-direct pressuring zone decreases with the increase of stress.

Keywords

• self-lubricating
• liner
• stress
• friction
• wear