Abstract
This study was to examine the wear characteristics of an artificial hip joint on the exfoliation of adsorbed film by long-term simulator test and pin-on-disc test. Lubricant was a water-based liquid, and it contained principal constituents in synovial fluid. If a joint remains in a stationary state under heavy load from body weight, the lubricating condition is too severe to generate sufficient fluid film. However, the wear of UHMWPE cup decreased with the formation of transferred film. The bearing surface of the UHMWPE cup became differing contour in the different operating conditions of the sequence cycle and interruption cycle. The wear of UHMWPE pin decreased with the increase of contact pressure in pin-on-disc test. And, the formation of transferred film was observed on the bearing surface of Co-Cr-Mo alloy. Therefore, the transferred film at asperity level was thought to be effective on the decrease of wear in the severe condition with the exfoliation of synovial constituents.
